src/fileio.c

/* vi:set ts=8 sts=4 sw=4 noet:
 *
 * VIM - Vi IMproved	by Bram Moolenaar
 *
 * Do ":help uganda"  in Vim to read copying and usage conditions.
 * Do ":help credits" in Vim to see a list of people who contributed.
 * See README.txt for an overview of the Vim source code.
 */

/*
 * fileio.c: read from and write to a file
 */

#include "vim.h"

#if defined(__TANDEM) || defined(__MINT__)
# include <limits.h>		/* for SSIZE_MAX */
#endif

#if defined(HAVE_UTIME) && defined(HAVE_UTIME_H)
# include <utime.h>		/* for struct utimbuf */
#endif

#define BUFSIZE		8192	/* size of normal write buffer */
#define SMBUFSIZE	256	/* size of emergency write buffer */

/* Is there any system that doesn't have access()? */
#define USE_MCH_ACCESS

static char_u *next_fenc(char_u **pp);
#ifdef FEAT_EVAL
static char_u *readfile_charconvert(char_u *fname, char_u *fenc, int *fdp);
#endif
#ifdef FEAT_VIMINFO
static void check_marks_read(void);
#endif
#ifdef FEAT_CRYPT
static char_u *check_for_cryptkey(char_u *cryptkey, char_u *ptr, long *sizep, off_T *filesizep, int newfile, char_u *fname, int *did_ask);
#endif
static int set_rw_fname(char_u *fname, char_u *sfname);
static int msg_add_fileformat(int eol_type);
static void msg_add_eol(void);
static int check_mtime(buf_T *buf, stat_T *s);
static int time_differs(long t1, long t2);

#define HAS_BW_FLAGS
#define FIO_LATIN1	0x01	/* convert Latin1 */
#define FIO_UTF8	0x02	/* convert UTF-8 */
#define FIO_UCS2	0x04	/* convert UCS-2 */
#define FIO_UCS4	0x08	/* convert UCS-4 */
#define FIO_UTF16	0x10	/* convert UTF-16 */
#ifdef MSWIN
# define FIO_CODEPAGE	0x20	/* convert MS-Windows codepage */
# define FIO_PUT_CP(x) (((x) & 0xffff) << 16)	/* put codepage in top word */
# define FIO_GET_CP(x)	(((x)>>16) & 0xffff)	/* get codepage from top word */
#endif
#ifdef MACOS_CONVERT
# define FIO_MACROMAN	0x20	/* convert MacRoman */
#endif
#define FIO_ENDIAN_L	0x80	/* little endian */
#define FIO_ENCRYPTED	0x1000	/* encrypt written bytes */
#define FIO_NOCONVERT	0x2000	/* skip encoding conversion */
#define FIO_UCSBOM	0x4000	/* check for BOM at start of file */
#define FIO_ALL	-1	/* allow all formats */

/* When converting, a read() or write() may leave some bytes to be converted
 * for the next call.  The value is guessed... */
#define CONV_RESTLEN 30

/* We have to guess how much a sequence of bytes may expand when converting
 * with iconv() to be able to allocate a buffer. */
#define ICONV_MULT 8

/*
 * Structure to pass arguments from buf_write() to buf_write_bytes().
 */
struct bw_info
{
    int		bw_fd;		/* file descriptor */
    char_u	*bw_buf;	/* buffer with data to be written */
    int		bw_len;		/* length of data */
#ifdef HAS_BW_FLAGS
    int		bw_flags;	/* FIO_ flags */
#endif
#ifdef FEAT_CRYPT
    buf_T	*bw_buffer;	/* buffer being written */
#endif
    char_u	bw_rest[CONV_RESTLEN]; /* not converted bytes */
    int		bw_restlen;	/* nr of bytes in bw_rest[] */
    int		bw_first;	/* first write call */
    char_u	*bw_conv_buf;	/* buffer for writing converted chars */
    int		bw_conv_buflen; /* size of bw_conv_buf */
    int		bw_conv_error;	/* set for conversion error */
    linenr_T	bw_conv_error_lnum;  /* first line with error or zero */
    linenr_T	bw_start_lnum;  /* line number at start of buffer */
#ifdef USE_ICONV
    iconv_t	bw_iconv_fd;	/* descriptor for iconv() or -1 */
#endif
};

static int  buf_write_bytes(struct bw_info *ip);

static linenr_T readfile_linenr(linenr_T linecnt, char_u *p, char_u *endp);
static int ucs2bytes(unsigned c, char_u **pp, int flags);
static int need_conversion(char_u *fenc);
static int get_fio_flags(char_u *ptr);
static char_u *check_for_bom(char_u *p, long size, int *lenp, int flags);
static int make_bom(char_u *buf, char_u *name);
#ifdef MSWIN
static int get_win_fio_flags(char_u *ptr);
#endif
#ifdef MACOS_CONVERT
static int get_mac_fio_flags(char_u *ptr);
#endif
static char *e_auchangedbuf = N_("E812: Autocommands changed buffer or buffer name");

    void
filemess(
    buf_T	*buf,
    char_u	*name,
    char_u	*s,
    int		attr)
{
    int		msg_scroll_save;

    if (msg_silent != 0)
	return;
    msg_add_fname(buf, name);	    /* put file name in IObuff with quotes */
    /* If it's extremely long, truncate it. */
    if (STRLEN(IObuff) > IOSIZE - 80)
	IObuff[IOSIZE - 80] = NUL;
    STRCAT(IObuff, s);
    /*
     * For the first message may have to start a new line.
     * For further ones overwrite the previous one, reset msg_scroll before
     * calling filemess().
     */
    msg_scroll_save = msg_scroll;
    if (shortmess(SHM_OVERALL) && !exiting && p_verbose == 0)
	msg_scroll = FALSE;
    if (!msg_scroll)	/* wait a bit when overwriting an error msg */
	check_for_delay(FALSE);
    msg_start();
    msg_scroll = msg_scroll_save;
    msg_scrolled_ign = TRUE;
    /* may truncate the message to avoid a hit-return prompt */
    msg_outtrans_attr(msg_may_trunc(FALSE, IObuff), attr);
    msg_clr_eos();
    out_flush();
    msg_scrolled_ign = FALSE;
}

/*
 * Read lines from file "fname" into the buffer after line "from".
 *
 * 1. We allocate blocks with lalloc, as big as possible.
 * 2. Each block is filled with characters from the file with a single read().
 * 3. The lines are inserted in the buffer with ml_append().
 *
 * (caller must check that fname != NULL, unless READ_STDIN is used)
 *
 * "lines_to_skip" is the number of lines that must be skipped
 * "lines_to_read" is the number of lines that are appended
 * When not recovering lines_to_skip is 0 and lines_to_read MAXLNUM.
 *
 * flags:
 * READ_NEW	starting to edit a new buffer
 * READ_FILTER	reading filter output
 * READ_STDIN	read from stdin instead of a file
 * READ_BUFFER	read from curbuf instead of a file (converting after reading
 *		stdin)
 * READ_DUMMY	read into a dummy buffer (to check if file contents changed)
 * READ_KEEP_UNDO  don't clear undo info or read it from a file
 * READ_FIFO	read from fifo/socket instead of a file
 *
 * return FAIL for failure, NOTDONE for directory (failure), or OK
 */
    int
readfile(
    char_u	*fname,
    char_u	*sfname,
    linenr_T	from,
    linenr_T	lines_to_skip,
    linenr_T	lines_to_read,
    exarg_T	*eap,			/* can be NULL! */
    int		flags)
{
    int		fd = 0;
    int		newfile = (flags & READ_NEW);
    int		check_readonly;
    int		filtering = (flags & READ_FILTER);
    int		read_stdin = (flags & READ_STDIN);
    int		read_buffer = (flags & READ_BUFFER);
    int		read_fifo = (flags & READ_FIFO);
    int		set_options = newfile || read_buffer
					   || (eap != NULL && eap->read_edit);
    linenr_T	read_buf_lnum = 1;	/* next line to read from curbuf */
    colnr_T	read_buf_col = 0;	/* next char to read from this line */
    char_u	c;
    linenr_T	lnum = from;
    char_u	*ptr = NULL;		/* pointer into read buffer */
    char_u	*buffer = NULL;		/* read buffer */
    char_u	*new_buffer = NULL;	/* init to shut up gcc */
    char_u	*line_start = NULL;	/* init to shut up gcc */
    int		wasempty;		/* buffer was empty before reading */
    colnr_T	len;
    long	size = 0;
    char_u	*p;
    off_T	filesize = 0;
    int		skip_read = FALSE;
#ifdef FEAT_CRYPT
    char_u	*cryptkey = NULL;
    int		did_ask_for_key = FALSE;
#endif
#ifdef FEAT_PERSISTENT_UNDO
    context_sha256_T sha_ctx;
    int		read_undo_file = FALSE;
#endif
    int		split = 0;		/* number of split lines */
#define UNKNOWN	 0x0fffffff		/* file size is unknown */
    linenr_T	linecnt;
    int		error = FALSE;		/* errors encountered */
    int		ff_error = EOL_UNKNOWN; /* file format with errors */
    long	linerest = 0;		/* remaining chars in line */
#ifdef UNIX
    int		perm = 0;
    int		swap_mode = -1;		/* protection bits for swap file */
#else
    int		perm;
#endif
    int		fileformat = 0;		/* end-of-line format */
    int		keep_fileformat = FALSE;
    stat_T	st;
    int		file_readonly;
    linenr_T	skip_count = 0;
    linenr_T	read_count = 0;
    int		msg_save = msg_scroll;
    linenr_T	read_no_eol_lnum = 0;   /* non-zero lnum when last line of
					 * last read was missing the eol */
    int		try_mac;
    int		try_dos;
    int		try_unix;
    int		file_rewind = FALSE;
    int		can_retry;
    linenr_T	conv_error = 0;		/* line nr with conversion error */
    linenr_T	illegal_byte = 0;	/* line nr with illegal byte */
    int		keep_dest_enc = FALSE;	/* don't retry when char doesn't fit
					   in destination encoding */
    int		bad_char_behavior = BAD_REPLACE;
					/* BAD_KEEP, BAD_DROP or character to
					 * replace with */
    char_u	*tmpname = NULL;	/* name of 'charconvert' output file */
    int		fio_flags = 0;
    char_u	*fenc;			/* fileencoding to use */
    int		fenc_alloced;		/* fenc_next is in allocated memory */
    char_u	*fenc_next = NULL;	/* next item in 'fencs' or NULL */
    int		advance_fenc = FALSE;
    long	real_size = 0;
#ifdef USE_ICONV
    iconv_t	iconv_fd = (iconv_t)-1;	/* descriptor for iconv() or -1 */
# ifdef FEAT_EVAL
    int		did_iconv = FALSE;	/* TRUE when iconv() failed and trying
					   'charconvert' next */
# endif
#endif
    int		converted = FALSE;	/* TRUE if conversion done */
    int		notconverted = FALSE;	/* TRUE if conversion wanted but it
					   wasn't possible */
    char_u	conv_rest[CONV_RESTLEN];
    int		conv_restlen = 0;	/* nr of bytes in conv_rest[] */
    buf_T	*old_curbuf;
    char_u	*old_b_ffname;
    char_u	*old_b_fname;
    int		using_b_ffname;
    int		using_b_fname;

    au_did_filetype = FALSE; /* reset before triggering any autocommands */

    curbuf->b_no_eol_lnum = 0;	/* in case it was set by the previous read */

    /*
     * If there is no file name yet, use the one for the read file.
     * BF_NOTEDITED is set to reflect this.
     * Don't do this for a read from a filter.
     * Only do this when 'cpoptions' contains the 'f' flag.
     */
    if (curbuf->b_ffname == NULL
	    && !filtering
	    && fname != NULL
	    && vim_strchr(p_cpo, CPO_FNAMER) != NULL
	    && !(flags & READ_DUMMY))
    {
	if (set_rw_fname(fname, sfname) == FAIL)
	    return FAIL;
    }

    /* Remember the initial values of curbuf, curbuf->b_ffname and
     * curbuf->b_fname to detect whether they are altered as a result of
     * executing nasty autocommands.  Also check if "fname" and "sfname"
     * point to one of these values. */
    old_curbuf = curbuf;
    old_b_ffname = curbuf->b_ffname;
    old_b_fname = curbuf->b_fname;
    using_b_ffname = (fname == curbuf->b_ffname)
					      || (sfname == curbuf->b_ffname);
    using_b_fname = (fname == curbuf->b_fname) || (sfname == curbuf->b_fname);

    /* After reading a file the cursor line changes but we don't want to
     * display the line. */
    ex_no_reprint = TRUE;

    /* don't display the file info for another buffer now */
    need_fileinfo = FALSE;

    /*
     * For Unix: Use the short file name whenever possible.
     * Avoids problems with networks and when directory names are changed.
     * Don't do this for MS-DOS, a "cd" in a sub-shell may have moved us to
     * another directory, which we don't detect.
     */
    if (sfname == NULL)
	sfname = fname;
#if defined(UNIX)
    fname = sfname;
#endif

    /*
     * The BufReadCmd and FileReadCmd events intercept the reading process by
     * executing the associated commands instead.
     */
    if (!filtering && !read_stdin && !read_buffer)
    {
	pos_T	    pos;

	pos = curbuf->b_op_start;

	/* Set '[ mark to the line above where the lines go (line 1 if zero). */
	curbuf->b_op_start.lnum = ((from == 0) ? 1 : from);
	curbuf->b_op_start.col = 0;

	if (newfile)
	{
	    if (apply_autocmds_exarg(EVENT_BUFREADCMD, NULL, sfname,
							  FALSE, curbuf, eap))
#ifdef FEAT_EVAL
		return aborting() ? FAIL : OK;
#else
		return OK;
#endif
	}
	else if (apply_autocmds_exarg(EVENT_FILEREADCMD, sfname, sfname,
							    FALSE, NULL, eap))
#ifdef FEAT_EVAL
	    return aborting() ? FAIL : OK;
#else
	    return OK;
#endif

	curbuf->b_op_start = pos;
    }

    if ((shortmess(SHM_OVER) || curbuf->b_help) && p_verbose == 0)
	msg_scroll = FALSE;	/* overwrite previous file message */
    else
	msg_scroll = TRUE;	/* don't overwrite previous file message */

    /*
     * If the name ends in a path separator, we can't open it.  Check here,
     * because reading the file may actually work, but then creating the swap
     * file may destroy it!  Reported on MS-DOS and Win 95.
     * If the name is too long we might crash further on, quit here.
     */
    if (fname != NULL && *fname != NUL)
    {
	p = fname + STRLEN(fname);
	if (after_pathsep(fname, p) || STRLEN(fname) >= MAXPATHL)
	{
	    filemess(curbuf, fname, (char_u *)_("Illegal file name"), 0);
	    msg_end();
	    msg_scroll = msg_save;
	    return FAIL;
	}
    }

    if (!read_stdin && !read_buffer && !read_fifo)
    {
#ifdef UNIX
	/*
	 * On Unix it is possible to read a directory, so we have to
	 * check for it before the mch_open().
	 */
	perm = mch_getperm(fname);
	if (perm >= 0 && !S_ISREG(perm)		    /* not a regular file ... */
		      && !S_ISFIFO(perm)	    /* ... or fifo */
		      && !S_ISSOCK(perm)	    /* ... or socket */
# ifdef OPEN_CHR_FILES
		      && !(S_ISCHR(perm) && is_dev_fd_file(fname))
			/* ... or a character special file named /dev/fd/<n> */
# endif
						)
	{
	    int retval = FAIL;

	    if (S_ISDIR(perm))
	    {
		filemess(curbuf, fname, (char_u *)_("is a directory"), 0);
		retval = NOTDONE;
	    }
	    else
		filemess(curbuf, fname, (char_u *)_("is not a file"), 0);
	    msg_end();
	    msg_scroll = msg_save;
	    return retval;
	}
#endif
#if defined(MSWIN)
	/*
	 * MS-Windows allows opening a device, but we will probably get stuck
	 * trying to read it.
	 */
	if (!p_odev && mch_nodetype(fname) == NODE_WRITABLE)
	{
	    filemess(curbuf, fname, (char_u *)_("is a device (disabled with 'opendevice' option)"), 0);
	    msg_end();
	    msg_scroll = msg_save;
	    return FAIL;
	}
#endif
    }

    /* Set default or forced 'fileformat' and 'binary'. */
    set_file_options(set_options, eap);

    /*
     * When opening a new file we take the readonly flag from the file.
     * Default is r/w, can be set to r/o below.
     * Don't reset it when in readonly mode
     * Only set/reset b_p_ro when BF_CHECK_RO is set.
     */
    check_readonly = (newfile && (curbuf->b_flags & BF_CHECK_RO));
    if (check_readonly && !readonlymode)
	curbuf->b_p_ro = FALSE;

    if (newfile && !read_stdin && !read_buffer && !read_fifo)
    {
	/* Remember time of file. */
	if (mch_stat((char *)fname, &st) >= 0)
	{
	    buf_store_time(curbuf, &st, fname);
	    curbuf->b_mtime_read = curbuf->b_mtime;
#ifdef UNIX
	    /*
	     * Use the protection bits of the original file for the swap file.
	     * This makes it possible for others to read the name of the
	     * edited file from the swapfile, but only if they can read the
	     * edited file.
	     * Remove the "write" and "execute" bits for group and others
	     * (they must not write the swapfile).
	     * Add the "read" and "write" bits for the user, otherwise we may
	     * not be able to write to the file ourselves.
	     * Setting the bits is done below, after creating the swap file.
	     */
	    swap_mode = (st.st_mode & 0644) | 0600;
#endif
#ifdef FEAT_CW_EDITOR
	    /* Get the FSSpec on MacOS
	     * TODO: Update it properly when the buffer name changes
	     */
	    (void)GetFSSpecFromPath(curbuf->b_ffname, &curbuf->b_FSSpec);
#endif
#ifdef VMS
	    curbuf->b_fab_rfm = st.st_fab_rfm;
	    curbuf->b_fab_rat = st.st_fab_rat;
	    curbuf->b_fab_mrs = st.st_fab_mrs;
#endif
	}
	else
	{
	    curbuf->b_mtime = 0;
	    curbuf->b_mtime_read = 0;
	    curbuf->b_orig_size = 0;
	    curbuf->b_orig_mode = 0;
	}

	/* Reset the "new file" flag.  It will be set again below when the
	 * file doesn't exist. */
	curbuf->b_flags &= ~(BF_NEW | BF_NEW_W);
    }

/*
 * for UNIX: check readonly with perm and mch_access()
 * for Amiga: check readonly by trying to open the file for writing
 */
    file_readonly = FALSE;
    if (read_stdin)
    {
#if defined(MSWIN)
	/* Force binary I/O on stdin to avoid CR-LF -> LF conversion. */
	setmode(0, O_BINARY);
#endif
    }
    else if (!read_buffer)
    {
#ifdef USE_MCH_ACCESS
	if (
# ifdef UNIX
	    !(perm & 0222) ||
# endif
				mch_access((char *)fname, W_OK))
	    file_readonly = TRUE;
	fd = mch_open((char *)fname, O_RDONLY | O_EXTRA, 0);
#else
	if (!newfile
		|| readonlymode
		|| (fd = mch_open((char *)fname, O_RDWR | O_EXTRA, 0)) < 0)
	{
	    file_readonly = TRUE;
	    /* try to open ro */
	    fd = mch_open((char *)fname, O_RDONLY | O_EXTRA, 0);
	}
#endif
    }

    if (fd < 0)			    /* cannot open at all */
    {
#ifndef UNIX
	int	isdir_f;
#endif
	msg_scroll = msg_save;
#ifndef UNIX
	/*
	 * On Amiga we can't open a directory, check here.
	 */
	isdir_f = (mch_isdir(fname));
	perm = mch_getperm(fname);  /* check if the file exists */
	if (isdir_f)
	{
	    filemess(curbuf, sfname, (char_u *)_("is a directory"), 0);
	    curbuf->b_p_ro = TRUE;	/* must use "w!" now */
	}
	else
#endif
	    if (newfile)
	    {
		if (perm < 0
#ifdef ENOENT
			&& errno == ENOENT
#endif
		   )
		{
		    /*
		     * Set the 'new-file' flag, so that when the file has
		     * been created by someone else, a ":w" will complain.
		     */
		    curbuf->b_flags |= BF_NEW;

		    /* Create a swap file now, so that other Vims are warned
		     * that we are editing this file.  Don't do this for a
		     * "nofile" or "nowrite" buffer type. */
#ifdef FEAT_QUICKFIX
		    if (!bt_dontwrite(curbuf))
#endif
		    {
			check_need_swap(newfile);
			/* SwapExists autocommand may mess things up */
			if (curbuf != old_curbuf
				|| (using_b_ffname
					&& (old_b_ffname != curbuf->b_ffname))
				|| (using_b_fname
					 && (old_b_fname != curbuf->b_fname)))
			{
			    emsg(_(e_auchangedbuf));
			    return FAIL;
			}
		    }
		    if (dir_of_file_exists(fname))
			filemess(curbuf, sfname, (char_u *)_("[New File]"), 0);
		    else
			filemess(curbuf, sfname,
					   (char_u *)_("[New DIRECTORY]"), 0);
#ifdef FEAT_VIMINFO
		    /* Even though this is a new file, it might have been
		     * edited before and deleted.  Get the old marks. */
		    check_marks_read();
#endif
		    /* Set forced 'fileencoding'.  */
		    if (eap != NULL)
			set_forced_fenc(eap);
		    apply_autocmds_exarg(EVENT_BUFNEWFILE, sfname, sfname,
							  FALSE, curbuf, eap);
		    /* remember the current fileformat */
		    save_file_ff(curbuf);

#if defined(FEAT_EVAL)
		    if (aborting())   /* autocmds may abort script processing */
			return FAIL;
#endif
		    return OK;	    /* a new file is not an error */
		}
		else
		{
		    filemess(curbuf, sfname, (char_u *)(
# ifdef EFBIG
			    (errno == EFBIG) ? _("[File too big]") :
# endif
# ifdef EOVERFLOW
			    (errno == EOVERFLOW) ? _("[File too big]") :
# endif
						_("[Permission Denied]")), 0);
		    curbuf->b_p_ro = TRUE;	/* must use "w!" now */
		}
	    }

	return FAIL;
    }

    /*
     * Only set the 'ro' flag for readonly files the first time they are
     * loaded.	Help files always get readonly mode
     */
    if ((check_readonly && file_readonly) || curbuf->b_help)
	curbuf->b_p_ro = TRUE;

    if (set_options)
    {
	/* Don't change 'eol' if reading from buffer as it will already be
	 * correctly set when reading stdin. */
	if (!read_buffer)
	{
	    curbuf->b_p_eol = TRUE;
	    curbuf->b_start_eol = TRUE;
	}
	curbuf->b_p_bomb = FALSE;
	curbuf->b_start_bomb = FALSE;
    }

    /* Create a swap file now, so that other Vims are warned that we are
     * editing this file.
     * Don't do this for a "nofile" or "nowrite" buffer type. */
#ifdef FEAT_QUICKFIX
    if (!bt_dontwrite(curbuf))
#endif
    {
	check_need_swap(newfile);
	if (!read_stdin && (curbuf != old_curbuf
		|| (using_b_ffname && (old_b_ffname != curbuf->b_ffname))
		|| (using_b_fname && (old_b_fname != curbuf->b_fname))))
	{
	    emsg(_(e_auchangedbuf));
	    if (!read_buffer)
		close(fd);
	    return FAIL;
	}
#ifdef UNIX
	/* Set swap file protection bits after creating it. */
	if (swap_mode > 0 && curbuf->b_ml.ml_mfp != NULL
			  && curbuf->b_ml.ml_mfp->mf_fname != NULL)
	{
	    char_u *swap_fname = curbuf->b_ml.ml_mfp->mf_fname;

	    /*
	     * If the group-read bit is set but not the world-read bit, then
	     * the group must be equal to the group of the original file.  If
	     * we can't make that happen then reset the group-read bit.  This
	     * avoids making the swap file readable to more users when the
	     * primary group of the user is too permissive.
	     */
	    if ((swap_mode & 044) == 040)
	    {
		stat_T	swap_st;

		if (mch_stat((char *)swap_fname, &swap_st) >= 0
			&& st.st_gid != swap_st.st_gid
# ifdef HAVE_FCHOWN
			&& fchown(curbuf->b_ml.ml_mfp->mf_fd, -1, st.st_gid)
									  == -1
# endif
		   )
		    swap_mode &= 0600;
	    }

	    (void)mch_setperm(swap_fname, (long)swap_mode);
	}
#endif
    }

    // If "Quit" selected at ATTENTION dialog, don't load the file
    if (swap_exists_action == SEA_QUIT)
    {
	if (!read_buffer && !read_stdin)
	    close(fd);
	return FAIL;
    }

    ++no_wait_return;	    /* don't wait for return yet */

    /*
     * Set '[ mark to the line above where the lines go (line 1 if zero).
     */
    curbuf->b_op_start.lnum = ((from == 0) ? 1 : from);
    curbuf->b_op_start.col = 0;

    try_mac = (vim_strchr(p_ffs, 'm') != NULL);
    try_dos = (vim_strchr(p_ffs, 'd') != NULL);
    try_unix = (vim_strchr(p_ffs, 'x') != NULL);

    if (!read_buffer)
    {
	int	m = msg_scroll;
	int	n = msg_scrolled;

	/*
	 * The file must be closed again, the autocommands may want to change
	 * the file before reading it.
	 */
	if (!read_stdin)
	    close(fd);		/* ignore errors */

	/*
	 * The output from the autocommands should not overwrite anything and
	 * should not be overwritten: Set msg_scroll, restore its value if no
	 * output was done.
	 */
	msg_scroll = TRUE;
	if (filtering)
	    apply_autocmds_exarg(EVENT_FILTERREADPRE, NULL, sfname,
							  FALSE, curbuf, eap);
	else if (read_stdin)
	    apply_autocmds_exarg(EVENT_STDINREADPRE, NULL, sfname,
							  FALSE, curbuf, eap);
	else if (newfile)
	    apply_autocmds_exarg(EVENT_BUFREADPRE, NULL, sfname,
							  FALSE, curbuf, eap);
	else
	    apply_autocmds_exarg(EVENT_FILEREADPRE, sfname, sfname,
							    FALSE, NULL, eap);
	/* autocommands may have changed it */
	try_mac = (vim_strchr(p_ffs, 'm') != NULL);
	try_dos = (vim_strchr(p_ffs, 'd') != NULL);
	try_unix = (vim_strchr(p_ffs, 'x') != NULL);

	if (msg_scrolled == n)
	    msg_scroll = m;

#ifdef FEAT_EVAL
	if (aborting())	    /* autocmds may abort script processing */
	{
	    --no_wait_return;
	    msg_scroll = msg_save;
	    curbuf->b_p_ro = TRUE;	/* must use "w!" now */
	    return FAIL;
	}
#endif
	/*
	 * Don't allow the autocommands to change the current buffer.
	 * Try to re-open the file.
	 *
	 * Don't allow the autocommands to change the buffer name either
	 * (cd for example) if it invalidates fname or sfname.
	 */
	if (!read_stdin && (curbuf != old_curbuf
		|| (using_b_ffname && (old_b_ffname != curbuf->b_ffname))
		|| (using_b_fname && (old_b_fname != curbuf->b_fname))
		|| (fd = mch_open((char *)fname, O_RDONLY | O_EXTRA, 0)) < 0))
	{
	    --no_wait_return;
	    msg_scroll = msg_save;
	    if (fd < 0)
		emsg(_("E200: *ReadPre autocommands made the file unreadable"));
	    else
		emsg(_("E201: *ReadPre autocommands must not change current buffer"));
	    curbuf->b_p_ro = TRUE;	/* must use "w!" now */
	    return FAIL;
	}
    }

    /* Autocommands may add lines to the file, need to check if it is empty */
    wasempty = (curbuf->b_ml.ml_flags & ML_EMPTY);

    if (!recoverymode && !filtering && !(flags & READ_DUMMY))
    {
	/*
	 * Show the user that we are busy reading the input.  Sometimes this
	 * may take a while.  When reading from stdin another program may
	 * still be running, don't move the cursor to the last line, unless
	 * always using the GUI.
	 */
	if (read_stdin)
	{
	    if (!is_not_a_term())
	    {
#ifndef ALWAYS_USE_GUI
# ifdef VIMDLL
		if (!gui.in_use)
# endif
		    mch_msg(_("Vim: Reading from stdin...\n"));
#endif
#ifdef FEAT_GUI
		/* Also write a message in the GUI window, if there is one. */
		if (gui.in_use && !gui.dying && !gui.starting)
		{
		    p = (char_u *)_("Reading from stdin...");
		    gui_write(p, (int)STRLEN(p));
		}
#endif
	    }
	}
	else if (!read_buffer)
	    filemess(curbuf, sfname, (char_u *)"", 0);
    }

    msg_scroll = FALSE;			/* overwrite the file message */

    /*
     * Set linecnt now, before the "retry" caused by a wrong guess for
     * fileformat, and after the autocommands, which may change them.
     */
    linecnt = curbuf->b_ml.ml_line_count;

    /* "++bad=" argument. */
    if (eap != NULL && eap->bad_char != 0)
    {
	bad_char_behavior = eap->bad_char;
	if (set_options)
	    curbuf->b_bad_char = eap->bad_char;
    }
    else
	curbuf->b_bad_char = 0;

    /*
     * Decide which 'encoding' to use or use first.
     */
    if (eap != NULL && eap->force_enc != 0)
    {
	fenc = enc_canonize(eap->cmd + eap->force_enc);
	fenc_alloced = TRUE;
	keep_dest_enc = TRUE;
    }
    else if (curbuf->b_p_bin)
    {
	fenc = (char_u *)"";		/* binary: don't convert */
	fenc_alloced = FALSE;
    }
    else if (curbuf->b_help)
    {
	char_u	    firstline[80];
	int	    fc;

	/* Help files are either utf-8 or latin1.  Try utf-8 first, if this
	 * fails it must be latin1.
	 * Always do this when 'encoding' is "utf-8".  Otherwise only do
	 * this when needed to avoid [converted] remarks all the time.
	 * It is needed when the first line contains non-ASCII characters.
	 * That is only in *.??x files. */
	fenc = (char_u *)"latin1";
	c = enc_utf8;
	if (!c && !read_stdin)
	{
	    fc = fname[STRLEN(fname) - 1];
	    if (TOLOWER_ASC(fc) == 'x')
	    {
		/* Read the first line (and a bit more).  Immediately rewind to
		 * the start of the file.  If the read() fails "len" is -1. */
		len = read_eintr(fd, firstline, 80);
		vim_lseek(fd, (off_T)0L, SEEK_SET);
		for (p = firstline; p < firstline + len; ++p)
		    if (*p >= 0x80)
		    {
			c = TRUE;
			break;
		    }
	    }
	}

	if (c)
	{
	    fenc_next = fenc;
	    fenc = (char_u *)"utf-8";

	    /* When the file is utf-8 but a character doesn't fit in
	     * 'encoding' don't retry.  In help text editing utf-8 bytes
	     * doesn't make sense. */
	    if (!enc_utf8)
		keep_dest_enc = TRUE;
	}
	fenc_alloced = FALSE;
    }
    else if (*p_fencs == NUL)
    {
	fenc = curbuf->b_p_fenc;	/* use format from buffer */
	fenc_alloced = FALSE;
    }
    else
    {
	fenc_next = p_fencs;		/* try items in 'fileencodings' */
	fenc = next_fenc(&fenc_next);
	fenc_alloced = TRUE;
    }

    /*
     * Jump back here to retry reading the file in different ways.
     * Reasons to retry:
     * - encoding conversion failed: try another one from "fenc_next"
     * - BOM detected and fenc was set, need to setup conversion
     * - "fileformat" check failed: try another
     *
     * Variables set for special retry actions:
     * "file_rewind"	Rewind the file to start reading it again.
     * "advance_fenc"	Advance "fenc" using "fenc_next".
     * "skip_read"	Re-use already read bytes (BOM detected).
     * "did_iconv"	iconv() conversion failed, try 'charconvert'.
     * "keep_fileformat" Don't reset "fileformat".
     *
     * Other status indicators:
     * "tmpname"	When != NULL did conversion with 'charconvert'.
     *			Output file has to be deleted afterwards.
     * "iconv_fd"	When != -1 did conversion with iconv().
     */
retry:

    if (file_rewind)
    {
	if (read_buffer)
	{
	    read_buf_lnum = 1;
	    read_buf_col = 0;
	}
	else if (read_stdin || vim_lseek(fd, (off_T)0L, SEEK_SET) != 0)
	{
	    /* Can't rewind the file, give up. */
	    error = TRUE;
	    goto failed;
	}
	/* Delete the previously read lines. */
	while (lnum > from)
	    ml_delete(lnum--, FALSE);
	file_rewind = FALSE;
	if (set_options)
	{
	    curbuf->b_p_bomb = FALSE;
	    curbuf->b_start_bomb = FALSE;
	}
	conv_error = 0;
    }

    /*
     * When retrying with another "fenc" and the first time "fileformat"
     * will be reset.
     */
    if (keep_fileformat)
	keep_fileformat = FALSE;
    else
    {
	if (eap != NULL && eap->force_ff != 0)
	{
	    fileformat = get_fileformat_force(curbuf, eap);
	    try_unix = try_dos = try_mac = FALSE;
	}
	else if (curbuf->b_p_bin)
	    fileformat = EOL_UNIX;		/* binary: use Unix format */
	else if (*p_ffs == NUL)
	    fileformat = get_fileformat(curbuf);/* use format from buffer */
	else
	    fileformat = EOL_UNKNOWN;		/* detect from file */
    }

#ifdef USE_ICONV
    if (iconv_fd != (iconv_t)-1)
    {
	/* aborted conversion with iconv(), close the descriptor */
	iconv_close(iconv_fd);
	iconv_fd = (iconv_t)-1;
    }
#endif

    if (advance_fenc)
    {
	/*
	 * Try the next entry in 'fileencodings'.
	 */
	advance_fenc = FALSE;

	if (eap != NULL && eap->force_enc != 0)
	{
	    /* Conversion given with "++cc=" wasn't possible, read
	     * without conversion. */
	    notconverted = TRUE;
	    conv_error = 0;
	    if (fenc_alloced)
		vim_free(fenc);
	    fenc = (char_u *)"";
	    fenc_alloced = FALSE;
	}
	else
	{
	    if (fenc_alloced)
		vim_free(fenc);
	    if (fenc_next != NULL)
	    {
		fenc = next_fenc(&fenc_next);
		fenc_alloced = (fenc_next != NULL);
	    }
	    else
	    {
		fenc = (char_u *)"";
		fenc_alloced = FALSE;
	    }
	}
	if (tmpname != NULL)
	{
	    mch_remove(tmpname);		/* delete converted file */
	    VIM_CLEAR(tmpname);
	}
    }

    /*
     * Conversion may be required when the encoding of the file is different
     * from 'encoding' or 'encoding' is UTF-16, UCS-2 or UCS-4.
     */
    fio_flags = 0;
    converted = need_conversion(fenc);
    if (converted)
    {

	/* "ucs-bom" means we need to check the first bytes of the file
	 * for a BOM. */
	if (STRCMP(fenc, ENC_UCSBOM) == 0)
	    fio_flags = FIO_UCSBOM;

	/*
	 * Check if UCS-2/4 or Latin1 to UTF-8 conversion needs to be
	 * done.  This is handled below after read().  Prepare the
	 * fio_flags to avoid having to parse the string each time.
	 * Also check for Unicode to Latin1 conversion, because iconv()
	 * appears not to handle this correctly.  This works just like
	 * conversion to UTF-8 except how the resulting character is put in
	 * the buffer.
	 */
	else if (enc_utf8 || STRCMP(p_enc, "latin1") == 0)
	    fio_flags = get_fio_flags(fenc);

#ifdef MSWIN
	/*
	 * Conversion from an MS-Windows codepage to UTF-8 or another codepage
	 * is handled with MultiByteToWideChar().
	 */
	if (fio_flags == 0)
	    fio_flags = get_win_fio_flags(fenc);
#endif

#ifdef MACOS_CONVERT
	/* Conversion from Apple MacRoman to latin1 or UTF-8 */
	if (fio_flags == 0)
	    fio_flags = get_mac_fio_flags(fenc);
#endif

#ifdef USE_ICONV
	/*
	 * Try using iconv() if we can't convert internally.
	 */
	if (fio_flags == 0
# ifdef FEAT_EVAL
		&& !did_iconv
# endif
		)
	    iconv_fd = (iconv_t)my_iconv_open(
				  enc_utf8 ? (char_u *)"utf-8" : p_enc, fenc);
#endif

#ifdef FEAT_EVAL
	/*
	 * Use the 'charconvert' expression when conversion is required
	 * and we can't do it internally or with iconv().
	 */
	if (fio_flags == 0 && !read_stdin && !read_buffer && *p_ccv != NUL
						    && !read_fifo
# ifdef USE_ICONV
						    && iconv_fd == (iconv_t)-1
# endif
		)
	{
# ifdef USE_ICONV
	    did_iconv = FALSE;
# endif
	    /* Skip conversion when it's already done (retry for wrong
	     * "fileformat"). */
	    if (tmpname == NULL)
	    {
		tmpname = readfile_charconvert(fname, fenc, &fd);
		if (tmpname == NULL)
		{
		    /* Conversion failed.  Try another one. */
		    advance_fenc = TRUE;
		    if (fd < 0)
		    {
			/* Re-opening the original file failed! */
			emsg(_("E202: Conversion made file unreadable!"));
			error = TRUE;
			goto failed;
		    }
		    goto retry;
		}
	    }
	}
	else
#endif
	{
	    if (fio_flags == 0
#ifdef USE_ICONV
		    && iconv_fd == (iconv_t)-1
#endif
	       )
	    {
		/* Conversion wanted but we can't.
		 * Try the next conversion in 'fileencodings' */
		advance_fenc = TRUE;
		goto retry;
	    }
	}
    }

    /* Set "can_retry" when it's possible to rewind the file and try with
     * another "fenc" value.  It's FALSE when no other "fenc" to try, reading
     * stdin or fixed at a specific encoding. */
    can_retry = (*fenc != NUL && !read_stdin && !read_fifo && !keep_dest_enc);

    if (!skip_read)
    {
	linerest = 0;
	filesize = 0;
	skip_count = lines_to_skip;
	read_count = lines_to_read;
	conv_restlen = 0;
#ifdef FEAT_PERSISTENT_UNDO
	read_undo_file = (newfile && (flags & READ_KEEP_UNDO) == 0
				  && curbuf->b_ffname != NULL
				  && curbuf->b_p_udf
				  && !filtering
				  && !read_fifo
				  && !read_stdin
				  && !read_buffer);
	if (read_undo_file)
	    sha256_start(&sha_ctx);
#endif
#ifdef FEAT_CRYPT
	if (curbuf->b_cryptstate != NULL)
	{
	    /* Need to free the state, but keep the key, don't want to ask for
	     * it again. */
	    crypt_free_state(curbuf->b_cryptstate);
	    curbuf->b_cryptstate = NULL;
	}
#endif
    }

    while (!error && !got_int)
    {
	/*
	 * We allocate as much space for the file as we can get, plus
	 * space for the old line plus room for one terminating NUL.
	 * The amount is limited by the fact that read() only can read
	 * upto max_unsigned characters (and other things).
	 */
	if (!skip_read)
	{
#if defined(SSIZE_MAX) && (SSIZE_MAX < 0x10000L)
		size = SSIZE_MAX;		    /* use max I/O size, 52K */
#else
		/* Use buffer >= 64K.  Add linerest to double the size if the
		 * line gets very long, to avoid a lot of copying. But don't
		 * read more than 1 Mbyte at a time, so we can be interrupted.
		 */
		size = 0x10000L + linerest;
		if (size > 0x100000L)
		    size = 0x100000L;
#endif
	}

	/* Protect against the argument of lalloc() going negative. */
	if (size < 0 || size + linerest + 1 < 0 || linerest >= MAXCOL)
	{
	    ++split;
	    *ptr = NL;		    /* split line by inserting a NL */
	    size = 1;
	}
	else
	{
	    if (!skip_read)
	    {
		for ( ; size >= 10; size = (long)((long_u)size >> 1))
		{
		    if ((new_buffer = lalloc((long_u)(size + linerest + 1),
							      FALSE)) != NULL)
			break;
		}
		if (new_buffer == NULL)
		{
		    do_outofmem_msg((long_u)(size * 2 + linerest + 1));
		    error = TRUE;
		    break;
		}
		if (linerest)	/* copy characters from the previous buffer */
		    mch_memmove(new_buffer, ptr - linerest, (size_t)linerest);
		vim_free(buffer);
		buffer = new_buffer;
		ptr = buffer + linerest;
		line_start = buffer;

		/* May need room to translate into.
		 * For iconv() we don't really know the required space, use a
		 * factor ICONV_MULT.
		 * latin1 to utf-8: 1 byte becomes up to 2 bytes
		 * utf-16 to utf-8: 2 bytes become up to 3 bytes, 4 bytes
		 * become up to 4 bytes, size must be multiple of 2
		 * ucs-2 to utf-8: 2 bytes become up to 3 bytes, size must be
		 * multiple of 2
		 * ucs-4 to utf-8: 4 bytes become up to 6 bytes, size must be
		 * multiple of 4 */
		real_size = (int)size;
#ifdef USE_ICONV
		if (iconv_fd != (iconv_t)-1)
		    size = size / ICONV_MULT;
		else
#endif
		    if (fio_flags & FIO_LATIN1)
		    size = size / 2;
		else if (fio_flags & (FIO_UCS2 | FIO_UTF16))
		    size = (size * 2 / 3) & ~1;
		else if (fio_flags & FIO_UCS4)
		    size = (size * 2 / 3) & ~3;
		else if (fio_flags == FIO_UCSBOM)
		    size = size / ICONV_MULT;	/* worst case */
#ifdef MSWIN
		else if (fio_flags & FIO_CODEPAGE)
		    size = size / ICONV_MULT;	/* also worst case */
#endif
#ifdef MACOS_CONVERT
		else if (fio_flags & FIO_MACROMAN)
		    size = size / ICONV_MULT;	/* also worst case */
#endif

		if (conv_restlen > 0)
		{
		    /* Insert unconverted bytes from previous line. */
		    mch_memmove(ptr, conv_rest, conv_restlen);
		    ptr += conv_restlen;
		    size -= conv_restlen;
		}

		if (read_buffer)
		{
		    /*
		     * Read bytes from curbuf.  Used for converting text read
		     * from stdin.
		     */
		    if (read_buf_lnum > from)
			size = 0;
		    else
		    {
			int	n, ni;
			long	tlen;

			tlen = 0;
			for (;;)
			{
			    p = ml_get(read_buf_lnum) + read_buf_col;
			    n = (int)STRLEN(p);
			    if ((int)tlen + n + 1 > size)
			    {
				/* Filled up to "size", append partial line.
				 * Change NL to NUL to reverse the effect done
				 * below. */
				n = (int)(size - tlen);
				for (ni = 0; ni < n; ++ni)
				{
				    if (p[ni] == NL)
					ptr[tlen++] = NUL;
				    else
					ptr[tlen++] = p[ni];
				}
				read_buf_col += n;
				break;
			    }
			    else
			    {
				/* Append whole line and new-line.  Change NL
				 * to NUL to reverse the effect done below. */
				for (ni = 0; ni < n; ++ni)
				{
				    if (p[ni] == NL)
					ptr[tlen++] = NUL;
				    else
					ptr[tlen++] = p[ni];
				}
				ptr[tlen++] = NL;
				read_buf_col = 0;
				if (++read_buf_lnum > from)
				{
				    /* When the last line didn't have an
				     * end-of-line don't add it now either. */
				    if (!curbuf->b_p_eol)
					--tlen;
				    size = tlen;
				    break;
				}
			    }
			}
		    }
		}
		else
		{
		    /*
		     * Read bytes from the file.
		     */
		    size = read_eintr(fd, ptr, size);
		}

#ifdef FEAT_CRYPT
		/*
		 * At start of file: Check for magic number of encryption.
		 */
		if (filesize == 0 && size > 0)
		    cryptkey = check_for_cryptkey(cryptkey, ptr, &size,
						  &filesize, newfile, sfname,
						  &did_ask_for_key);
		/*
		 * Decrypt the read bytes.  This is done before checking for
		 * EOF because the crypt layer may be buffering.
		 */
		if (cryptkey != NULL && curbuf->b_cryptstate != NULL
								   && size > 0)
		{
# ifdef CRYPT_NOT_INPLACE
		    if (crypt_works_inplace(curbuf->b_cryptstate))
		    {
# endif
			crypt_decode_inplace(curbuf->b_cryptstate, ptr, size);
# ifdef CRYPT_NOT_INPLACE
		    }
		    else
		    {
			char_u	*newptr = NULL;
			int	decrypted_size;

			decrypted_size = crypt_decode_alloc(
				    curbuf->b_cryptstate, ptr, size, &newptr);

			/* If the crypt layer is buffering, not producing
			 * anything yet, need to read more. */
			if (decrypted_size == 0)
			    continue;

			if (linerest == 0)
			{
			    /* Simple case: reuse returned buffer (may be
			     * NULL, checked later). */
			    new_buffer = newptr;
			}
			else
			{
			    long_u	new_size;

			    /* Need new buffer to add bytes carried over. */
			    new_size = (long_u)(decrypted_size + linerest + 1);
			    new_buffer = lalloc(new_size, FALSE);
			    if (new_buffer == NULL)
			    {
				do_outofmem_msg(new_size);
				error = TRUE;
				break;
			    }

			    mch_memmove(new_buffer, buffer, linerest);
			    if (newptr != NULL)
				mch_memmove(new_buffer + linerest, newptr,
							      decrypted_size);
			}

			if (new_buffer != NULL)
			{
			    vim_free(buffer);
			    buffer = new_buffer;
			    new_buffer = NULL;
			    line_start = buffer;
			    ptr = buffer + linerest;
			}
			size = decrypted_size;
		    }
# endif
		}
#endif

		if (size <= 0)
		{
		    if (size < 0)		    /* read error */
			error = TRUE;
		    else if (conv_restlen > 0)
		    {
			/*
			 * Reached end-of-file but some trailing bytes could
			 * not be converted.  Truncated file?
			 */

			/* When we did a conversion report an error. */
			if (fio_flags != 0
#ifdef USE_ICONV
				|| iconv_fd != (iconv_t)-1
#endif
			   )
			{
			    if (can_retry)
				goto rewind_retry;
			    if (conv_error == 0)
				conv_error = curbuf->b_ml.ml_line_count
								- linecnt + 1;
			}
			/* Remember the first linenr with an illegal byte */
			else if (illegal_byte == 0)
			    illegal_byte = curbuf->b_ml.ml_line_count
								- linecnt + 1;
			if (bad_char_behavior == BAD_DROP)
			{
			    *(ptr - conv_restlen) = NUL;
			    conv_restlen = 0;
			}
			else
			{
			    /* Replace the trailing bytes with the replacement
			     * character if we were converting; if we weren't,
			     * leave the UTF8 checking code to do it, as it
			     * works slightly differently. */
			    if (bad_char_behavior != BAD_KEEP && (fio_flags != 0
#ifdef USE_ICONV
				    || iconv_fd != (iconv_t)-1
#endif
			       ))
			    {
				while (conv_restlen > 0)
				{
				    *(--ptr) = bad_char_behavior;
				    --conv_restlen;
				}
			    }
			    fio_flags = 0;	/* don't convert this */
#ifdef USE_ICONV
			    if (iconv_fd != (iconv_t)-1)
			    {
				iconv_close(iconv_fd);
				iconv_fd = (iconv_t)-1;
			    }
#endif
			}
		    }
		}
	    }
	    skip_read = FALSE;

	    /*
	     * At start of file (or after crypt magic number): Check for BOM.
	     * Also check for a BOM for other Unicode encodings, but not after
	     * converting with 'charconvert' or when a BOM has already been
	     * found.
	     */
	    if ((filesize == 0
#ifdef FEAT_CRYPT
		   || (cryptkey != NULL
			&& filesize == crypt_get_header_len(
						 crypt_get_method_nr(curbuf)))
#endif
		       )
		    && (fio_flags == FIO_UCSBOM
			|| (!curbuf->b_p_bomb
			    && tmpname == NULL
			    && (*fenc == 'u' || (*fenc == NUL && enc_utf8)))))
	    {
		char_u	*ccname;
		int	blen;

		/* no BOM detection in a short file or in binary mode */
		if (size < 2 || curbuf->b_p_bin)
		    ccname = NULL;
		else
		    ccname = check_for_bom(ptr, size, &blen,
		      fio_flags == FIO_UCSBOM ? FIO_ALL : get_fio_flags(fenc));
		if (ccname != NULL)
		{
		    /* Remove BOM from the text */
		    filesize += blen;
		    size -= blen;
		    mch_memmove(ptr, ptr + blen, (size_t)size);
		    if (set_options)
		    {
			curbuf->b_p_bomb = TRUE;
			curbuf->b_start_bomb = TRUE;
		    }
		}

		if (fio_flags == FIO_UCSBOM)
		{
		    if (ccname == NULL)
		    {
			/* No BOM detected: retry with next encoding. */
			advance_fenc = TRUE;
		    }
		    else
		    {
			/* BOM detected: set "fenc" and jump back */
			if (fenc_alloced)
			    vim_free(fenc);
			fenc = ccname;
			fenc_alloced = FALSE;
		    }
		    /* retry reading without getting new bytes or rewinding */
		    skip_read = TRUE;
		    goto retry;
		}
	    }

	    /* Include not converted bytes. */
	    ptr -= conv_restlen;
	    size += conv_restlen;
	    conv_restlen = 0;
	    /*
	     * Break here for a read error or end-of-file.
	     */
	    if (size <= 0)
		break;


#ifdef USE_ICONV
	    if (iconv_fd != (iconv_t)-1)
	    {
		/*
		 * Attempt conversion of the read bytes to 'encoding' using
		 * iconv().
		 */
		const char	*fromp;
		char		*top;
		size_t		from_size;
		size_t		to_size;

		fromp = (char *)ptr;
		from_size = size;
		ptr += size;
		top = (char *)ptr;
		to_size = real_size - size;

		/*
		 * If there is conversion error or not enough room try using
		 * another conversion.  Except for when there is no
		 * alternative (help files).
		 */
		while ((iconv(iconv_fd, (void *)&fromp, &from_size,
							       &top, &to_size)
			    == (size_t)-1 && ICONV_ERRNO != ICONV_EINVAL)
						  || from_size > CONV_RESTLEN)
		{
		    if (can_retry)
			goto rewind_retry;
		    if (conv_error == 0)
			conv_error = readfile_linenr(linecnt,
							  ptr, (char_u *)top);

		    /* Deal with a bad byte and continue with the next. */
		    ++fromp;
		    --from_size;
		    if (bad_char_behavior == BAD_KEEP)
		    {
			*top++ = *(fromp - 1);
			--to_size;
		    }
		    else if (bad_char_behavior != BAD_DROP)
		    {
			*top++ = bad_char_behavior;
			--to_size;
		    }
		}

		if (from_size > 0)
		{
		    /* Some remaining characters, keep them for the next
		     * round. */
		    mch_memmove(conv_rest, (char_u *)fromp, from_size);
		    conv_restlen = (int)from_size;
		}

		/* move the linerest to before the converted characters */
		line_start = ptr - linerest;
		mch_memmove(line_start, buffer, (size_t)linerest);
		size = (long)((char_u *)top - ptr);
	    }
#endif

#ifdef MSWIN
	    if (fio_flags & FIO_CODEPAGE)
	    {
		char_u	*src, *dst;
		WCHAR	ucs2buf[3];
		int	ucs2len;
		int	codepage = FIO_GET_CP(fio_flags);
		int	bytelen;
		int	found_bad;
		char	replstr[2];

		/*
		 * Conversion from an MS-Windows codepage or UTF-8 to UTF-8 or
		 * a codepage, using standard MS-Windows functions.  This
		 * requires two steps:
		 * 1. convert from 'fileencoding' to ucs-2
		 * 2. convert from ucs-2 to 'encoding'
		 *
		 * Because there may be illegal bytes AND an incomplete byte
		 * sequence at the end, we may have to do the conversion one
		 * character at a time to get it right.
		 */

		/* Replacement string for WideCharToMultiByte(). */
		if (bad_char_behavior > 0)
		    replstr[0] = bad_char_behavior;
		else
		    replstr[0] = '?';
		replstr[1] = NUL;

		/*
		 * Move the bytes to the end of the buffer, so that we have
		 * room to put the result at the start.
		 */
		src = ptr + real_size - size;
		mch_memmove(src, ptr, size);

		/*
		 * Do the conversion.
		 */
		dst = ptr;
		size = size;
		while (size > 0)
		{
		    found_bad = FALSE;

#  ifdef CP_UTF8	/* VC 4.1 doesn't define CP_UTF8 */
		    if (codepage == CP_UTF8)
		    {
			/* Handle CP_UTF8 input ourselves to be able to handle
			 * trailing bytes properly.
			 * Get one UTF-8 character from src. */
			bytelen = (int)utf_ptr2len_len(src, size);
			if (bytelen > size)
			{
			    /* Only got some bytes of a character.  Normally
			     * it's put in "conv_rest", but if it's too long
			     * deal with it as if they were illegal bytes. */
			    if (bytelen <= CONV_RESTLEN)
				break;

			    /* weird overlong byte sequence */
			    bytelen = size;
			    found_bad = TRUE;
			}
			else
			{
			    int	    u8c = utf_ptr2char(src);

			    if (u8c > 0xffff || (*src >= 0x80 && bytelen == 1))
				found_bad = TRUE;
			    ucs2buf[0] = u8c;
			    ucs2len = 1;
			}
		    }
		    else
#  endif
		    {
			/* We don't know how long the byte sequence is, try
			 * from one to three bytes. */
			for (bytelen = 1; bytelen <= size && bytelen <= 3;
								    ++bytelen)
			{
			    ucs2len = MultiByteToWideChar(codepage,
							 MB_ERR_INVALID_CHARS,
							 (LPCSTR)src, bytelen,
								   ucs2buf, 3);
			    if (ucs2len > 0)
				break;
			}
			if (ucs2len == 0)
			{
			    /* If we have only one byte then it's probably an
			     * incomplete byte sequence.  Otherwise discard
			     * one byte as a bad character. */
			    if (size == 1)
				break;
			    found_bad = TRUE;
			    bytelen = 1;
			}
		    }

		    if (!found_bad)
		    {
			int	i;

			/* Convert "ucs2buf[ucs2len]" to 'enc' in "dst". */
			if (enc_utf8)
			{
			    /* From UCS-2 to UTF-8.  Cannot fail. */
			    for (i = 0; i < ucs2len; ++i)
				dst += utf_char2bytes(ucs2buf[i], dst);
			}
			else
			{
			    BOOL	bad = FALSE;
			    int		dstlen;

			    /* From UCS-2 to "enc_codepage".  If the
			     * conversion uses the default character "?",
			     * the data doesn't fit in this encoding. */
			    dstlen = WideCharToMultiByte(enc_codepage, 0,
				    (LPCWSTR)ucs2buf, ucs2len,
				    (LPSTR)dst, (int)(src - dst),
				    replstr, &bad);
			    if (bad)
				found_bad = TRUE;
			    else
				dst += dstlen;
			}
		    }

		    if (found_bad)
		    {
			/* Deal with bytes we can't convert. */
			if (can_retry)
			    goto rewind_retry;
			if (conv_error == 0)
			    conv_error = readfile_linenr(linecnt, ptr, dst);
			if (bad_char_behavior != BAD_DROP)
			{
			    if (bad_char_behavior == BAD_KEEP)
			    {
				mch_memmove(dst, src, bytelen);
				dst += bytelen;
			    }
			    else
				*dst++ = bad_char_behavior;
			}
		    }

		    src += bytelen;
		    size -= bytelen;
		}

		if (size > 0)
		{
		    /* An incomplete byte sequence remaining. */
		    mch_memmove(conv_rest, src, size);
		    conv_restlen = size;
		}

		/* The new size is equal to how much "dst" was advanced. */
		size = (long)(dst - ptr);
	    }
	    else
#endif
#ifdef MACOS_CONVERT
	    if (fio_flags & FIO_MACROMAN)
	    {
		/*
		 * Conversion from Apple MacRoman char encoding to UTF-8 or
		 * latin1.  This is in os_mac_conv.c.
		 */
		if (macroman2enc(ptr, &size, real_size) == FAIL)
		    goto rewind_retry;
	    }
	    else
#endif
	    if (fio_flags != 0)
	    {
		int	u8c;
		char_u	*dest;
		char_u	*tail = NULL;

		/*
		 * "enc_utf8" set: Convert Unicode or Latin1 to UTF-8.
		 * "enc_utf8" not set: Convert Unicode to Latin1.
		 * Go from end to start through the buffer, because the number
		 * of bytes may increase.
		 * "dest" points to after where the UTF-8 bytes go, "p" points
		 * to after the next character to convert.
		 */
		dest = ptr + real_size;
		if (fio_flags == FIO_LATIN1 || fio_flags == FIO_UTF8)
		{
		    p = ptr + size;
		    if (fio_flags == FIO_UTF8)
		    {
			/* Check for a trailing incomplete UTF-8 sequence */
			tail = ptr + size - 1;
			while (tail > ptr && (*tail & 0xc0) == 0x80)
			    --tail;
			if (tail + utf_byte2len(*tail) <= ptr + size)
			    tail = NULL;
			else
			    p = tail;
		    }
		}
		else if (fio_flags & (FIO_UCS2 | FIO_UTF16))
		{
		    /* Check for a trailing byte */
		    p = ptr + (size & ~1);
		    if (size & 1)
			tail = p;
		    if ((fio_flags & FIO_UTF16) && p > ptr)
		    {
			/* Check for a trailing leading word */
			if (fio_flags & FIO_ENDIAN_L)
			{
			    u8c = (*--p << 8);
			    u8c += *--p;
			}
			else
			{
			    u8c = *--p;
			    u8c += (*--p << 8);
			}
			if (u8c >= 0xd800 && u8c <= 0xdbff)
			    tail = p;
			else
			    p += 2;
		    }
		}
		else /*  FIO_UCS4 */
		{
		    /* Check for trailing 1, 2 or 3 bytes */
		    p = ptr + (size & ~3);
		    if (size & 3)
			tail = p;
		}

		/* If there is a trailing incomplete sequence move it to
		 * conv_rest[]. */
		if (tail != NULL)
		{
		    conv_restlen = (int)((ptr + size) - tail);
		    mch_memmove(conv_rest, (char_u *)tail, conv_restlen);
		    size -= conv_restlen;
		}


		while (p > ptr)
		{
		    if (fio_flags & FIO_LATIN1)
			u8c = *--p;
		    else if (fio_flags & (FIO_UCS2 | FIO_UTF16))
		    {
			if (fio_flags & FIO_ENDIAN_L)
			{
			    u8c = (*--p << 8);
			    u8c += *--p;
			}
			else
			{
			    u8c = *--p;
			    u8c += (*--p << 8);
			}
			if ((fio_flags & FIO_UTF16)
					    && u8c >= 0xdc00 && u8c <= 0xdfff)
			{
			    int u16c;

			    if (p == ptr)
			    {
				/* Missing leading word. */
				if (can_retry)
				    goto rewind_retry;
				if (conv_error == 0)
				    conv_error = readfile_linenr(linecnt,
								      ptr, p);
				if (bad_char_behavior == BAD_DROP)
				    continue;
				if (bad_char_behavior != BAD_KEEP)
				    u8c = bad_char_behavior;
			    }

			    /* found second word of double-word, get the first
			     * word and compute the resulting character */
			    if (fio_flags & FIO_ENDIAN_L)
			    {
				u16c = (*--p << 8);
				u16c += *--p;
			    }
			    else
			    {
				u16c = *--p;
				u16c += (*--p << 8);
			    }
			    u8c = 0x10000 + ((u16c & 0x3ff) << 10)
							      + (u8c & 0x3ff);

			    /* Check if the word is indeed a leading word. */
			    if (u16c < 0xd800 || u16c > 0xdbff)
			    {
				if (can_retry)
				    goto rewind_retry;
				if (conv_error == 0)
				    conv_error = readfile_linenr(linecnt,
								      ptr, p);
				if (bad_char_behavior == BAD_DROP)
				    continue;
				if (bad_char_behavior != BAD_KEEP)
				    u8c = bad_char_behavior;
			    }
			}
		    }
		    else if (fio_flags & FIO_UCS4)
		    {
			if (fio_flags & FIO_ENDIAN_L)
			{
			    u8c = (unsigned)*--p << 24;
			    u8c += (unsigned)*--p << 16;
			    u8c += (unsigned)*--p << 8;
			    u8c += *--p;
			}
			else	/* big endian */
			{
			    u8c = *--p;
			    u8c += (unsigned)*--p << 8;
			    u8c += (unsigned)*--p << 16;
			    u8c += (unsigned)*--p << 24;
			}
		    }
		    else    /* UTF-8 */
		    {
			if (*--p < 0x80)
			    u8c = *p;
			else
			{
			    len = utf_head_off(ptr, p);
			    p -= len;
			    u8c = utf_ptr2char(p);
			    if (len == 0)
			    {
				/* Not a valid UTF-8 character, retry with
				 * another fenc when possible, otherwise just
				 * report the error. */
				if (can_retry)
				    goto rewind_retry;
				if (conv_error == 0)
				    conv_error = readfile_linenr(linecnt,
								      ptr, p);
				if (bad_char_behavior == BAD_DROP)
				    continue;
				if (bad_char_behavior != BAD_KEEP)
				    u8c = bad_char_behavior;
			    }
			}
		    }
		    if (enc_utf8)	/* produce UTF-8 */
		    {
			dest -= utf_char2len(u8c);
			(void)utf_char2bytes(u8c, dest);
		    }
		    else		/* produce Latin1 */
		    {
			--dest;
			if (u8c >= 0x100)
			{
			    /* character doesn't fit in latin1, retry with
			     * another fenc when possible, otherwise just
			     * report the error. */
			    if (can_retry)
				goto rewind_retry;
			    if (conv_error == 0)
				conv_error = readfile_linenr(linecnt, ptr, p);
			    if (bad_char_behavior == BAD_DROP)
				++dest;
			    else if (bad_char_behavior == BAD_KEEP)
				*dest = u8c;
			    else if (eap != NULL && eap->bad_char != 0)
				*dest = bad_char_behavior;
			    else
				*dest = 0xBF;
			}
			else
			    *dest = u8c;
		    }
		}

		/* move the linerest to before the converted characters */
		line_start = dest - linerest;
		mch_memmove(line_start, buffer, (size_t)linerest);
		size = (long)((ptr + real_size) - dest);
		ptr = dest;
	    }
	    else if (enc_utf8 && !curbuf->b_p_bin)
	    {
		int  incomplete_tail = FALSE;

		/* Reading UTF-8: Check if the bytes are valid UTF-8. */
		for (p = ptr; ; ++p)
		{
		    int	 todo = (int)((ptr + size) - p);
		    int	 l;

		    if (todo <= 0)
			break;
		    if (*p >= 0x80)
		    {
			/* A length of 1 means it's an illegal byte.  Accept
			 * an incomplete character at the end though, the next
			 * read() will get the next bytes, we'll check it
			 * then. */
			l = utf_ptr2len_len(p, todo);
			if (l > todo && !incomplete_tail)
			{
			    /* Avoid retrying with a different encoding when
			     * a truncated file is more likely, or attempting
			     * to read the rest of an incomplete sequence when
			     * we have already done so. */
			    if (p > ptr || filesize > 0)
				incomplete_tail = TRUE;
			    /* Incomplete byte sequence, move it to conv_rest[]
			     * and try to read the rest of it, unless we've
			     * already done so. */
			    if (p > ptr)
			    {
				conv_restlen = todo;
				mch_memmove(conv_rest, p, conv_restlen);
				size -= conv_restlen;
				break;
			    }
			}
			if (l == 1 || l > todo)
			{
			    /* Illegal byte.  If we can try another encoding
			     * do that, unless at EOF where a truncated
			     * file is more likely than a conversion error. */
			    if (can_retry && !incomplete_tail)
				break;
#ifdef USE_ICONV
			    /* When we did a conversion report an error. */
			    if (iconv_fd != (iconv_t)-1 && conv_error == 0)
				conv_error = readfile_linenr(linecnt, ptr, p);
#endif
			    /* Remember the first linenr with an illegal byte */
			    if (conv_error == 0 && illegal_byte == 0)
				illegal_byte = readfile_linenr(linecnt, ptr, p);

			    /* Drop, keep or replace the bad byte. */
			    if (bad_char_behavior == BAD_DROP)
			    {
				mch_memmove(p, p + 1, todo - 1);
				--p;
				--size;
			    }
			    else if (bad_char_behavior != BAD_KEEP)
				*p = bad_char_behavior;
			}
			else
			    p += l - 1;
		    }
		}
		if (p < ptr + size && !incomplete_tail)
		{
		    /* Detected a UTF-8 error. */
rewind_retry:
		    /* Retry reading with another conversion. */
#if defined(FEAT_EVAL) && defined(USE_ICONV)
		    if (*p_ccv != NUL && iconv_fd != (iconv_t)-1)
			/* iconv() failed, try 'charconvert' */
			did_iconv = TRUE;
		    else
#endif
			/* use next item from 'fileencodings' */
			advance_fenc = TRUE;
		    file_rewind = TRUE;
		    goto retry;
		}
	    }

	    /* count the number of characters (after conversion!) */
	    filesize += size;

	    /*
	     * when reading the first part of a file: guess EOL type
	     */
	    if (fileformat == EOL_UNKNOWN)
	    {
		/* First try finding a NL, for Dos and Unix */
		if (try_dos || try_unix)
		{
		    /* Reset the carriage return counter. */
		    if (try_mac)
			try_mac = 1;

		    for (p = ptr; p < ptr + size; ++p)
		    {
			if (*p == NL)
			{
			    if (!try_unix
				    || (try_dos && p > ptr && p[-1] == CAR))
				fileformat = EOL_DOS;
			    else
				fileformat = EOL_UNIX;
			    break;
			}
			else if (*p == CAR && try_mac)
			    try_mac++;
		    }

		    /* Don't give in to EOL_UNIX if EOL_MAC is more likely */
		    if (fileformat == EOL_UNIX && try_mac)
		    {
			/* Need to reset the counters when retrying fenc. */
			try_mac = 1;
			try_unix = 1;
			for (; p >= ptr && *p != CAR; p--)
			    ;
			if (p >= ptr)
			{
			    for (p = ptr; p < ptr + size; ++p)
			    {
				if (*p == NL)
				    try_unix++;
				else if (*p == CAR)
				    try_mac++;
			    }
			    if (try_mac > try_unix)
				fileformat = EOL_MAC;
			}
		    }
		    else if (fileformat == EOL_UNKNOWN && try_mac == 1)
			/* Looking for CR but found no end-of-line markers at
			 * all: use the default format. */
			fileformat = default_fileformat();
		}

		/* No NL found: may use Mac format */
		if (fileformat == EOL_UNKNOWN && try_mac)
		    fileformat = EOL_MAC;

		/* Still nothing found?  Use first format in 'ffs' */
		if (fileformat == EOL_UNKNOWN)
		    fileformat = default_fileformat();

		/* if editing a new file: may set p_tx and p_ff */
		if (set_options)
		    set_fileformat(fileformat, OPT_LOCAL);
	    }
	}

	/*
	 * This loop is executed once for every character read.
	 * Keep it fast!
	 */
	if (fileformat == EOL_MAC)
	{
	    --ptr;
	    while (++ptr, --size >= 0)
	    {
		/* catch most common case first */
		if ((c = *ptr) != NUL && c != CAR && c != NL)
		    continue;
		if (c == NUL)
		    *ptr = NL;	/* NULs are replaced by newlines! */
		else if (c == NL)
		    *ptr = CAR;	/* NLs are replaced by CRs! */
		else
		{
		    if (skip_count == 0)
		    {
			*ptr = NUL;	    /* end of line */
			len = (colnr_T) (ptr - line_start + 1);
			if (ml_append(lnum, line_start, len, newfile) == FAIL)
			{
			    error = TRUE;
			    break;
			}
#ifdef FEAT_PERSISTENT_UNDO
			if (read_undo_file)
			    sha256_update(&sha_ctx, line_start, len);
#endif
			++lnum;
			if (--read_count == 0)
			{
			    error = TRUE;	/* break loop */
			    line_start = ptr;	/* nothing left to write */
			    break;
			}
		    }
		    else
			--skip_count;
		    line_start = ptr + 1;
		}
	    }
	}
	else
	{
	    --ptr;
	    while (++ptr, --size >= 0)
	    {
		if ((c = *ptr) != NUL && c != NL)  /* catch most common case */
		    continue;
		if (c == NUL)
		    *ptr = NL;	/* NULs are replaced by newlines! */
		else
		{
		    if (skip_count == 0)
		    {
			*ptr = NUL;		/* end of line */
			len = (colnr_T)(ptr - line_start + 1);
			if (fileformat == EOL_DOS)
			{
			    if (ptr > line_start && ptr[-1] == CAR)
			    {
				/* remove CR before NL */
				ptr[-1] = NUL;
				--len;
			    }
			    /*
			     * Reading in Dos format, but no CR-LF found!
			     * When 'fileformats' includes "unix", delete all
			     * the lines read so far and start all over again.
			     * Otherwise give an error message later.
			     */
			    else if (ff_error != EOL_DOS)
			    {
				if (   try_unix
				    && !read_stdin
				    && (read_buffer
					|| vim_lseek(fd, (off_T)0L, SEEK_SET)
									  == 0))
				{
				    fileformat = EOL_UNIX;
				    if (set_options)
					set_fileformat(EOL_UNIX, OPT_LOCAL);
				    file_rewind = TRUE;
				    keep_fileformat = TRUE;
				    goto retry;
				}
				ff_error = EOL_DOS;
			    }
			}
			if (ml_append(lnum, line_start, len, newfile) == FAIL)
			{
			    error = TRUE;
			    break;
			}
#ifdef FEAT_PERSISTENT_UNDO
			if (read_undo_file)
			    sha256_update(&sha_ctx, line_start, len);
#endif
			++lnum;
			if (--read_count == 0)
			{
			    error = TRUE;	    /* break loop */
			    line_start = ptr;	/* nothing left to write */
			    break;
			}
		    }
		    else
			--skip_count;
		    line_start = ptr + 1;
		}
	    }
	}
	linerest = (long)(ptr - line_start);
	ui_breakcheck();
    }

failed:
    /* not an error, max. number of lines reached */
    if (error && read_count == 0)
	error = FALSE;

    /*
     * If we get EOF in the middle of a line, note the fact and
     * complete the line ourselves.
     * In Dos format ignore a trailing CTRL-Z, unless 'binary' set.
     */
    if (!error
	    && !got_int
	    && linerest != 0
	    && !(!curbuf->b_p_bin
		&& fileformat == EOL_DOS
		&& *line_start == Ctrl_Z
		&& ptr == line_start + 1))
    {
	/* remember for when writing */
	if (set_options)
	    curbuf->b_p_eol = FALSE;
	*ptr = NUL;
	len = (colnr_T)(ptr - line_start + 1);
	if (ml_append(lnum, line_start, len, newfile) == FAIL)
	    error = TRUE;
	else
	{
#ifdef FEAT_PERSISTENT_UNDO
	    if (read_undo_file)
		sha256_update(&sha_ctx, line_start, len);
#endif
	    read_no_eol_lnum = ++lnum;
	}
    }

    if (set_options)
	save_file_ff(curbuf);		/* remember the current file format */

#ifdef FEAT_CRYPT
    if (curbuf->b_cryptstate != NULL)
    {
	crypt_free_state(curbuf->b_cryptstate);
	curbuf->b_cryptstate = NULL;
    }
    if (cryptkey != NULL && cryptkey != curbuf->b_p_key)
	crypt_free_key(cryptkey);
    /* Don't set cryptkey to NULL, it's used below as a flag that
     * encryption was used. */
#endif

    /* If editing a new file: set 'fenc' for the current buffer.
     * Also for ":read ++edit file". */
    if (set_options)
	set_string_option_direct((char_u *)"fenc", -1, fenc,
						       OPT_FREE|OPT_LOCAL, 0);
    if (fenc_alloced)
	vim_free(fenc);
#ifdef USE_ICONV
    if (iconv_fd != (iconv_t)-1)
	iconv_close(iconv_fd);
#endif

    if (!read_buffer && !read_stdin)
	close(fd);				/* errors are ignored */
#ifdef HAVE_FD_CLOEXEC
    else
    {
	int fdflags = fcntl(fd, F_GETFD);
	if (fdflags >= 0 && (fdflags & FD_CLOEXEC) == 0)
	    (void)fcntl(fd, F_SETFD, fdflags | FD_CLOEXEC);
    }
#endif
    vim_free(buffer);

#ifdef HAVE_DUP
    if (read_stdin)
    {
	/* Use stderr for stdin, makes shell commands work. */
	close(0);
	vim_ignored = dup(2);
    }
#endif

    if (tmpname != NULL)
    {
	mch_remove(tmpname);		/* delete converted file */
	vim_free(tmpname);
    }
    --no_wait_return;			/* may wait for return now */

    /*
     * In recovery mode everything but autocommands is skipped.
     */
    if (!recoverymode)
    {
	/* need to delete the last line, which comes from the empty buffer */
	if (newfile && wasempty && !(curbuf->b_ml.ml_flags & ML_EMPTY))
	{
#ifdef FEAT_NETBEANS_INTG
	    netbeansFireChanges = 0;
#endif
	    ml_delete(curbuf->b_ml.ml_line_count, FALSE);
#ifdef FEAT_NETBEANS_INTG
	    netbeansFireChanges = 1;
#endif
	    --linecnt;
	}
	linecnt = curbuf->b_ml.ml_line_count - linecnt;
	if (filesize == 0)
	    linecnt = 0;
	if (newfile || read_buffer)
	{
	    redraw_curbuf_later(NOT_VALID);
#ifdef FEAT_DIFF
	    /* After reading the text into the buffer the diff info needs to
	     * be updated. */
	    diff_invalidate(curbuf);
#endif
#ifdef FEAT_FOLDING
	    /* All folds in the window are invalid now.  Mark them for update
	     * before triggering autocommands. */
	    foldUpdateAll(curwin);
#endif
	}
	else if (linecnt)		/* appended at least one line */
	    appended_lines_mark(from, linecnt);

#ifndef ALWAYS_USE_GUI
	/*
	 * If we were reading from the same terminal as where messages go,
	 * the screen will have been messed up.
	 * Switch on raw mode now and clear the screen.
	 */
	if (read_stdin)
	{
	    settmode(TMODE_RAW);	/* set to raw mode */
	    starttermcap();
	    screenclear();
	}
#endif

	if (got_int)
	{
	    if (!(flags & READ_DUMMY))
	    {
		filemess(curbuf, sfname, (char_u *)_(e_interr), 0);
		if (newfile)
		    curbuf->b_p_ro = TRUE;	/* must use "w!" now */
	    }
	    msg_scroll = msg_save;
#ifdef FEAT_VIMINFO
	    check_marks_read();
#endif
	    return OK;		/* an interrupt isn't really an error */
	}

	if (!filtering && !(flags & READ_DUMMY))
	{
	    msg_add_fname(curbuf, sfname);   /* fname in IObuff with quotes */
	    c = FALSE;

#ifdef UNIX
	    if (S_ISFIFO(perm))			    /* fifo */
	    {
		STRCAT(IObuff, _("[fifo]"));
		c = TRUE;
	    }
	    if (S_ISSOCK(perm))			    /* or socket */
	    {
		STRCAT(IObuff, _("[socket]"));
		c = TRUE;
	    }
# ifdef OPEN_CHR_FILES
	    if (S_ISCHR(perm))			    /* or character special */
	    {
		STRCAT(IObuff, _("[character special]"));
		c = TRUE;
	    }
# endif
#endif
	    if (curbuf->b_p_ro)
	    {
		STRCAT(IObuff, shortmess(SHM_RO) ? _("[RO]") : _("[readonly]"));
		c = TRUE;
	    }
	    if (read_no_eol_lnum)
	    {
		msg_add_eol();
		c = TRUE;
	    }
	    if (ff_error == EOL_DOS)
	    {
		STRCAT(IObuff, _("[CR missing]"));
		c = TRUE;
	    }
	    if (split)
	    {
		STRCAT(IObuff, _("[long lines split]"));
		c = TRUE;
	    }
	    if (notconverted)
	    {
		STRCAT(IObuff, _("[NOT converted]"));
		c = TRUE;
	    }
	    else if (converted)
	    {
		STRCAT(IObuff, _("[converted]"));
		c = TRUE;
	    }
#ifdef FEAT_CRYPT
	    if (cryptkey != NULL)
	    {
		crypt_append_msg(curbuf);
		c = TRUE;
	    }
#endif
	    if (conv_error != 0)
	    {
		sprintf((char *)IObuff + STRLEN(IObuff),
		       _("[CONVERSION ERROR in line %ld]"), (long)conv_error);
		c = TRUE;
	    }
	    else if (illegal_byte > 0)
	    {
		sprintf((char *)IObuff + STRLEN(IObuff),
			 _("[ILLEGAL BYTE in line %ld]"), (long)illegal_byte);
		c = TRUE;
	    }
	    else if (error)
	    {
		STRCAT(IObuff, _("[READ ERRORS]"));
		c = TRUE;
	    }
	    if (msg_add_fileformat(fileformat))
		c = TRUE;
#ifdef FEAT_CRYPT
	    if (cryptkey != NULL)
		msg_add_lines(c, (long)linecnt, filesize
			 - crypt_get_header_len(crypt_get_method_nr(curbuf)));
	    else
#endif
		msg_add_lines(c, (long)linecnt, filesize);

	    VIM_CLEAR(keep_msg);
	    msg_scrolled_ign = TRUE;
#ifdef ALWAYS_USE_GUI
	    /* Don't show the message when reading stdin, it would end up in a
	     * message box (which might be shown when exiting!) */
	    if (read_stdin || read_buffer)
		p = msg_may_trunc(FALSE, IObuff);
	    else
#endif
		p = (char_u *)msg_trunc_attr((char *)IObuff, FALSE, 0);
	    if (read_stdin || read_buffer || restart_edit != 0
		    || (msg_scrolled != 0 && !need_wait_return))
		/* Need to repeat the message after redrawing when:
		 * - When reading from stdin (the screen will be cleared next).
		 * - When restart_edit is set (otherwise there will be a delay
		 *   before redrawing).
		 * - When the screen was scrolled but there is no wait-return
		 *   prompt. */
		set_keep_msg(p, 0);
	    msg_scrolled_ign = FALSE;
	}

	/* with errors writing the file requires ":w!" */
	if (newfile && (error
		    || conv_error != 0
		    || (illegal_byte > 0 && bad_char_behavior != BAD_KEEP)))
	    curbuf->b_p_ro = TRUE;

	u_clearline();	    /* cannot use "U" command after adding lines */

	/*
	 * In Ex mode: cursor at last new line.
	 * Otherwise: cursor at first new line.
	 */
	if (exmode_active)
	    curwin->w_cursor.lnum = from + linecnt;
	else
	    curwin->w_cursor.lnum = from + 1;
	check_cursor_lnum();
	beginline(BL_WHITE | BL_FIX);	    /* on first non-blank */

	/*
	 * Set '[ and '] marks to the newly read lines.
	 */
	curbuf->b_op_start.lnum = from + 1;
	curbuf->b_op_start.col = 0;
	curbuf->b_op_end.lnum = from + linecnt;
	curbuf->b_op_end.col = 0;

#ifdef MSWIN
	/*
	 * Work around a weird problem: When a file has two links (only
	 * possible on NTFS) and we write through one link, then stat() it
	 * through the other link, the timestamp information may be wrong.
	 * It's correct again after reading the file, thus reset the timestamp
	 * here.
	 */
	if (newfile && !read_stdin && !read_buffer
					 && mch_stat((char *)fname, &st) >= 0)
	{
	    buf_store_time(curbuf, &st, fname);
	    curbuf->b_mtime_read = curbuf->b_mtime;
	}
#endif
    }
    msg_scroll = msg_save;

#ifdef FEAT_VIMINFO
    /*
     * Get the marks before executing autocommands, so they can be used there.
     */
    check_marks_read();
#endif

    /*
     * We remember if the last line of the read didn't have
     * an eol even when 'binary' is off, to support turning 'fixeol' off,
     * or writing the read again with 'binary' on.  The latter is required
     * for ":autocmd FileReadPost *.gz set bin|'[,']!gunzip" to work.
     */
    curbuf->b_no_eol_lnum = read_no_eol_lnum;

    /* When reloading a buffer put the cursor at the first line that is
     * different. */
    if (flags & READ_KEEP_UNDO)
	u_find_first_changed();

#ifdef FEAT_PERSISTENT_UNDO
    /*
     * When opening a new file locate undo info and read it.
     */
    if (read_undo_file)
    {
	char_u	hash[UNDO_HASH_SIZE];

	sha256_finish(&sha_ctx, hash);
	u_read_undo(NULL, hash, fname);
    }
#endif

    if (!read_stdin && !read_fifo && (!read_buffer || sfname != NULL))
    {
	int m = msg_scroll;
	int n = msg_scrolled;

	/* Save the fileformat now, otherwise the buffer will be considered
	 * modified if the format/encoding was automatically detected. */
	if (set_options)
	    save_file_ff(curbuf);

	/*
	 * The output from the autocommands should not overwrite anything and
	 * should not be overwritten: Set msg_scroll, restore its value if no
	 * output was done.
	 */
	msg_scroll = TRUE;
	if (filtering)
	    apply_autocmds_exarg(EVENT_FILTERREADPOST, NULL, sfname,
							  FALSE, curbuf, eap);
	else if (newfile || (read_buffer && sfname != NULL))
	{
	    apply_autocmds_exarg(EVENT_BUFREADPOST, NULL, sfname,
							  FALSE, curbuf, eap);
	    if (!au_did_filetype && *curbuf->b_p_ft != NUL)
		/*
		 * EVENT_FILETYPE was not triggered but the buffer already has a
		 * filetype. Trigger EVENT_FILETYPE using the existing filetype.
		 */
		apply_autocmds(EVENT_FILETYPE, curbuf->b_p_ft, curbuf->b_fname,
			TRUE, curbuf);
	}
	else
	    apply_autocmds_exarg(EVENT_FILEREADPOST, sfname, sfname,
							    FALSE, NULL, eap);
	if (msg_scrolled == n)
	    msg_scroll = m;
# ifdef FEAT_EVAL
	if (aborting())	    /* autocmds may abort script processing */
	    return FAIL;
# endif
    }

    if (recoverymode && error)
	return FAIL;
    return OK;
}

#if defined(OPEN_CHR_FILES) || defined(PROTO)
/*
 * Returns TRUE if the file name argument is of the form "/dev/fd/\d\+",
 * which is the name of files used for process substitution output by
 * some shells on some operating systems, e.g., bash on SunOS.
 * Do not accept "/dev/fd/[012]", opening these may hang Vim.
 */
    int
is_dev_fd_file(char_u *fname)
{
    return (STRNCMP(fname, "/dev/fd/", 8) == 0
	    && VIM_ISDIGIT(fname[8])
	    && *skipdigits(fname + 9) == NUL
	    && (fname[9] != NUL
		|| (fname[8] != '0' && fname[8] != '1' && fname[8] != '2')));
}
#endif

/*
 * From the current line count and characters read after that, estimate the
 * line number where we are now.
 * Used for error messages that include a line number.
 */
    static linenr_T
readfile_linenr(
    linenr_T	linecnt,	/* line count before reading more bytes */
    char_u	*p,		/* start of more bytes read */
    char_u	*endp)		/* end of more bytes read */
{
    char_u	*s;
    linenr_T	lnum;

    lnum = curbuf->b_ml.ml_line_count - linecnt + 1;
    for (s = p; s < endp; ++s)
	if (*s == '\n')
	    ++lnum;
    return lnum;
}

/*
 * Fill "*eap" to force the 'fileencoding', 'fileformat' and 'binary to be
 * equal to the buffer "buf".  Used for calling readfile().
 * Returns OK or FAIL.
 */
    int
prep_exarg(exarg_T *eap, buf_T *buf)
{
    eap->cmd = alloc(15 + (unsigned)STRLEN(buf->b_p_fenc));
    if (eap->cmd == NULL)
	return FAIL;

    sprintf((char *)eap->cmd, "e ++enc=%s", buf->b_p_fenc);
    eap->force_enc = 8;
    eap->bad_char = buf->b_bad_char;
    eap->force_ff = *buf->b_p_ff;

    eap->force_bin = buf->b_p_bin ? FORCE_BIN : FORCE_NOBIN;
    eap->read_edit = FALSE;
    eap->forceit = FALSE;
    return OK;
}

/*
 * Set default or forced 'fileformat' and 'binary'.
 */
    void
set_file_options(int set_options, exarg_T *eap)
{
    /* set default 'fileformat' */
    if (set_options)
    {
	if (eap != NULL && eap->force_ff != 0)
	    set_fileformat(get_fileformat_force(curbuf, eap), OPT_LOCAL);
	else if (*p_ffs != NUL)
	    set_fileformat(default_fileformat(), OPT_LOCAL);
    }

    /* set or reset 'binary' */
    if (eap != NULL && eap->force_bin != 0)
    {
	int	oldval = curbuf->b_p_bin;

	curbuf->b_p_bin = (eap->force_bin == FORCE_BIN);
	set_options_bin(oldval, curbuf->b_p_bin, OPT_LOCAL);
    }
}

/*
 * Set forced 'fileencoding'.
 */
    void
set_forced_fenc(exarg_T *eap)
{
    if (eap->force_enc != 0)
    {
	char_u *fenc = enc_canonize(eap->cmd + eap->force_enc);

	if (fenc != NULL)
	    set_string_option_direct((char_u *)"fenc", -1,
				 fenc, OPT_FREE|OPT_LOCAL, 0);
	vim_free(fenc);
    }
}

/*
 * Find next fileencoding to use from 'fileencodings'.
 * "pp" points to fenc_next.  It's advanced to the next item.
 * When there are no more items, an empty string is returned and *pp is set to
 * NULL.
 * When *pp is not set to NULL, the result is in allocated memory.
 */
    static char_u *
next_fenc(char_u **pp)
{
    char_u	*p;
    char_u	*r;

    if (**pp == NUL)
    {
	*pp = NULL;
	return (char_u *)"";
    }
    p = vim_strchr(*pp, ',');
    if (p == NULL)
    {
	r = enc_canonize(*pp);
	*pp += STRLEN(*pp);
    }
    else
    {
	r = vim_strnsave(*pp, (int)(p - *pp));
	*pp = p + 1;
	if (r != NULL)
	{
	    p = enc_canonize(r);
	    vim_free(r);
	    r = p;
	}
    }
    if (r == NULL)	/* out of memory */
    {
	r = (char_u *)"";
	*pp = NULL;
    }
    return r;
}

#ifdef FEAT_EVAL
/*
 * Convert a file with the 'charconvert' expression.
 * This closes the file which is to be read, converts it and opens the
 * resulting file for reading.
 * Returns name of the resulting converted file (the caller should delete it
 * after reading it).
 * Returns NULL if the conversion failed ("*fdp" is not set) .
 */
    static char_u *
readfile_charconvert(
    char_u	*fname,		/* name of input file */
    char_u	*fenc,		/* converted from */
    int		*fdp)		/* in/out: file descriptor of file */
{
    char_u	*tmpname;
    char	*errmsg = NULL;

    tmpname = vim_tempname('r', FALSE);
    if (tmpname == NULL)
	errmsg = _("Can't find temp file for conversion");
    else
    {
	close(*fdp);		/* close the input file, ignore errors */
	*fdp = -1;
	if (eval_charconvert(fenc, enc_utf8 ? (char_u *)"utf-8" : p_enc,
						      fname, tmpname) == FAIL)
	    errmsg = _("Conversion with 'charconvert' failed");
	if (errmsg == NULL && (*fdp = mch_open((char *)tmpname,
						  O_RDONLY | O_EXTRA, 0)) < 0)
	    errmsg = _("can't read output of 'charconvert'");
    }

    if (errmsg != NULL)
    {
	/* Don't use emsg(), it breaks mappings, the retry with
	 * another type of conversion might still work. */
	msg(errmsg);
	if (tmpname != NULL)
	{
	    mch_remove(tmpname);	/* delete converted file */
	    VIM_CLEAR(tmpname);
	}
    }

    /* If the input file is closed, open it (caller should check for error). */
    if (*fdp < 0)
	*fdp = mch_open((char *)fname, O_RDONLY | O_EXTRA, 0);

    return tmpname;
}
#endif


#ifdef FEAT_VIMINFO
/*
 * Read marks for the current buffer from the viminfo file, when we support
 * buffer marks and the buffer has a name.
 */
    static void
check_marks_read(void)
{
    if (!curbuf->b_marks_read && get_viminfo_parameter('\'') > 0
						  && curbuf->b_ffname != NULL)
	read_viminfo(NULL, VIF_WANT_MARKS);

    /* Always set b_marks_read; needed when 'viminfo' is changed to include
     * the ' parameter after opening a buffer. */
    curbuf->b_marks_read = TRUE;
}
#endif

#if defined(FEAT_CRYPT) || defined(PROTO)
/*
 * Check for magic number used for encryption.  Applies to the current buffer.
 * If found, the magic number is removed from ptr[*sizep] and *sizep and
 * *filesizep are updated.
 * Return the (new) encryption key, NULL for no encryption.
 */
    static char_u *
check_for_cryptkey(
    char_u	*cryptkey,	/* previous encryption key or NULL */
    char_u	*ptr,		/* pointer to read bytes */
    long	*sizep,		/* length of read bytes */
    off_T	*filesizep,	/* nr of bytes used from file */
    int		newfile,	/* editing a new buffer */
    char_u	*fname,		/* file name to display */
    int		*did_ask)	/* flag: whether already asked for key */
{
    int method = crypt_method_nr_from_magic((char *)ptr, *sizep);
    int b_p_ro = curbuf->b_p_ro;

    if (method >= 0)
    {
	/* Mark the buffer as read-only until the decryption has taken place.
	 * Avoids accidentally overwriting the file with garbage. */
	curbuf->b_p_ro = TRUE;

	/* Set the cryptmethod local to the buffer. */
	crypt_set_cm_option(curbuf, method);
	if (cryptkey == NULL && !*did_ask)
	{
	    if (*curbuf->b_p_key)
		cryptkey = curbuf->b_p_key;
	    else
	    {
		/* When newfile is TRUE, store the typed key in the 'key'
		 * option and don't free it.  bf needs hash of the key saved.
		 * Don't ask for the key again when first time Enter was hit.
		 * Happens when retrying to detect encoding. */
		smsg(_(need_key_msg), fname);
		msg_scroll = TRUE;
		crypt_check_method(method);
		cryptkey = crypt_get_key(newfile, FALSE);
		*did_ask = TRUE;

		/* check if empty key entered */
		if (cryptkey != NULL && *cryptkey == NUL)
		{
		    if (cryptkey != curbuf->b_p_key)
			vim_free(cryptkey);
		    cryptkey = NULL;
		}
	    }
	}

	if (cryptkey != NULL)
	{
	    int header_len;

	    curbuf->b_cryptstate = crypt_create_from_header(
						       method, cryptkey, ptr);
	    crypt_set_cm_option(curbuf, method);

	    /* Remove cryptmethod specific header from the text. */
	    header_len = crypt_get_header_len(method);
	    if (*sizep <= header_len)
		/* invalid header, buffer can't be encrypted */
		return NULL;
	    *filesizep += header_len;
	    *sizep -= header_len;
	    mch_memmove(ptr, ptr + header_len, (size_t)*sizep);

	    /* Restore the read-only flag. */
	    curbuf->b_p_ro = b_p_ro;
	}
    }
    /* When starting to edit a new file which does not have encryption, clear
     * the 'key' option, except when starting up (called with -x argument) */
    else if (newfile && *curbuf->b_p_key != NUL && !starting)
	set_option_value((char_u *)"key", 0L, (char_u *)"", OPT_LOCAL);

    return cryptkey;
}
#endif  /* FEAT_CRYPT */

#ifdef UNIX
    static void
set_file_time(
    char_u  *fname,
    time_t  atime,	    /* access time */
    time_t  mtime)	    /* modification time */
{
# if defined(HAVE_UTIME) && defined(HAVE_UTIME_H)
    struct utimbuf  buf;

    buf.actime	= atime;
    buf.modtime	= mtime;
    (void)utime((char *)fname, &buf);
# else
#  if defined(HAVE_UTIMES)
    struct timeval  tvp[2];

    tvp[0].tv_sec   = atime;
    tvp[0].tv_usec  = 0;
    tvp[1].tv_sec   = mtime;
    tvp[1].tv_usec  = 0;
#   ifdef NeXT
    (void)utimes((char *)fname, tvp);
#   else
    (void)utimes((char *)fname, (const struct timeval *)&tvp);
#   endif
#  endif
# endif
}
#endif /* UNIX */

#if defined(VMS) && !defined(MIN)
/* Older DECC compiler for VAX doesn't define MIN() */
# define MIN(a, b) ((a) < (b) ? (a) : (b))
#endif

/*
 * Return TRUE if a file appears to be read-only from the file permissions.
 */
    int
check_file_readonly(
    char_u	*fname,		/* full path to file */
    int		perm)		/* known permissions on file */
{
#ifndef USE_MCH_ACCESS
    int	    fd = 0;
#endif

    return (
#ifdef USE_MCH_ACCESS
# ifdef UNIX
	(perm & 0222) == 0 ||
# endif
	mch_access((char *)fname, W_OK)
#else
	(fd = mch_open((char *)fname, O_RDWR | O_EXTRA, 0)) < 0
					? TRUE : (close(fd), FALSE)
#endif
	);
}


/*
 * buf_write() - write to file "fname" lines "start" through "end"
 *
 * We do our own buffering here because fwrite() is so slow.
 *
 * If "forceit" is true, we don't care for errors when attempting backups.
 * In case of an error everything possible is done to restore the original
 * file.  But when "forceit" is TRUE, we risk losing it.
 *
 * When "reset_changed" is TRUE and "append" == FALSE and "start" == 1 and
 * "end" == curbuf->b_ml.ml_line_count, reset curbuf->b_changed.
 *
 * This function must NOT use NameBuff (because it's called by autowrite()).
 *
 * return FAIL for failure, OK otherwise
 */
    int
buf_write(
    buf_T	    *buf,
    char_u	    *fname,
    char_u	    *sfname,
    linenr_T	    start,
    linenr_T	    end,
    exarg_T	    *eap,		/* for forced 'ff' and 'fenc', can be
					   NULL! */
    int		    append,		/* append to the file */
    int		    forceit,
    int		    reset_changed,
    int		    filtering)
{
    int		    fd;
    char_u	    *backup = NULL;
    int		    backup_copy = FALSE; /* copy the original file? */
    int		    dobackup;
    char_u	    *ffname;
    char_u	    *wfname = NULL;	/* name of file to write to */
    char_u	    *s;
    char_u	    *ptr;
    char_u	    c;
    int		    len;
    linenr_T	    lnum;
    long	    nchars;
    char_u	    *errmsg = NULL;
    int		    errmsg_allocated = FALSE;
    char_u	    *errnum = NULL;
    char_u	    *buffer;
    char_u	    smallbuf[SMBUFSIZE];
    char_u	    *backup_ext;
    int		    bufsize;
    long	    perm;		    /* file permissions */
    int		    retval = OK;
    int		    newfile = FALSE;	    /* TRUE if file doesn't exist yet */
    int		    msg_save = msg_scroll;
    int		    overwriting;	    /* TRUE if writing over original */
    int		    no_eol = FALSE;	    /* no end-of-line written */
    int		    device = FALSE;	    /* writing to a device */
    stat_T	    st_old;
    int		    prev_got_int = got_int;
    int		    checking_conversion;
    int		    file_readonly = FALSE;  /* overwritten file is read-only */
    static char	    *err_readonly = "is read-only (cannot override: \"W\" in 'cpoptions')";
#if defined(UNIX)			    /*XXX fix me sometime? */
    int		    made_writable = FALSE;  /* 'w' bit has been set */
#endif
					/* writing everything */
    int		    whole = (start == 1 && end == buf->b_ml.ml_line_count);
    linenr_T	    old_line_count = buf->b_ml.ml_line_count;
    int		    attr;
    int		    fileformat;
    int		    write_bin;
    struct bw_info  write_info;		/* info for buf_write_bytes() */
    int		    converted = FALSE;
    int		    notconverted = FALSE;
    char_u	    *fenc;		/* effective 'fileencoding' */
    char_u	    *fenc_tofree = NULL; /* allocated "fenc" */
#ifdef HAS_BW_FLAGS
    int		    wb_flags = 0;
#endif
#ifdef HAVE_ACL
    vim_acl_T	    acl = NULL;		/* ACL copied from original file to
					   backup or new file */
#endif
#ifdef FEAT_PERSISTENT_UNDO
    int		    write_undo_file = FALSE;
    context_sha256_T sha_ctx;
#endif
    unsigned int    bkc = get_bkc_value(buf);

    if (fname == NULL || *fname == NUL)	/* safety check */
	return FAIL;
    if (buf->b_ml.ml_mfp == NULL)
    {
	/* This can happen during startup when there is a stray "w" in the
	 * vimrc file. */
	emsg(_(e_emptybuf));
	return FAIL;
    }

    /*
     * Disallow writing from .exrc and .vimrc in current directory for
     * security reasons.
     */
    if (check_secure())
	return FAIL;

    /* Avoid a crash for a long name. */
    if (STRLEN(fname) >= MAXPATHL)
    {
	emsg(_(e_longname));
	return FAIL;
    }

    /* must init bw_conv_buf and bw_iconv_fd before jumping to "fail" */
    write_info.bw_conv_buf = NULL;
    write_info.bw_conv_error = FALSE;
    write_info.bw_conv_error_lnum = 0;
    write_info.bw_restlen = 0;
#ifdef USE_ICONV
    write_info.bw_iconv_fd = (iconv_t)-1;
#endif
#ifdef FEAT_CRYPT
    write_info.bw_buffer = buf;
#endif

    /* After writing a file changedtick changes but we don't want to display
     * the line. */
    ex_no_reprint = TRUE;

    /*
     * If there is no file name yet, use the one for the written file.
     * BF_NOTEDITED is set to reflect this (in case the write fails).
     * Don't do this when the write is for a filter command.
     * Don't do this when appending.
     * Only do this when 'cpoptions' contains the 'F' flag.
     */
    if (buf->b_ffname == NULL
	    && reset_changed
	    && whole
	    && buf == curbuf
#ifdef FEAT_QUICKFIX
	    && !bt_nofile(buf)
#endif
	    && !filtering
	    && (!append || vim_strchr(p_cpo, CPO_FNAMEAPP) != NULL)
	    && vim_strchr(p_cpo, CPO_FNAMEW) != NULL)
    {
	if (set_rw_fname(fname, sfname) == FAIL)
	    return FAIL;
	buf = curbuf;	    /* just in case autocmds made "buf" invalid */
    }

    if (sfname == NULL)
	sfname = fname;
    /*
     * For Unix: Use the short file name whenever possible.
     * Avoids problems with networks and when directory names are changed.
     * Don't do this for MS-DOS, a "cd" in a sub-shell may have moved us to
     * another directory, which we don't detect
     */
    ffname = fname;			    /* remember full fname */
#ifdef UNIX
    fname = sfname;
#endif

    if (buf->b_ffname != NULL && fnamecmp(ffname, buf->b_ffname) == 0)
	overwriting = TRUE;
    else
	overwriting = FALSE;

    if (exiting)
	settmode(TMODE_COOK);	    /* when exiting allow typeahead now */

    ++no_wait_return;		    /* don't wait for return yet */

    /*
     * Set '[ and '] marks to the lines to be written.
     */
    buf->b_op_start.lnum = start;
    buf->b_op_start.col = 0;
    buf->b_op_end.lnum = end;
    buf->b_op_end.col = 0;

    {
	aco_save_T	aco;
	int		buf_ffname = FALSE;
	int		buf_sfname = FALSE;
	int		buf_fname_f = FALSE;
	int		buf_fname_s = FALSE;
	int		did_cmd = FALSE;
	int		nofile_err = FALSE;
	int		empty_memline = (buf->b_ml.ml_mfp == NULL);
	bufref_T	bufref;

	/*
	 * Apply PRE autocommands.
	 * Set curbuf to the buffer to be written.
	 * Careful: The autocommands may call buf_write() recursively!
	 */
	if (ffname == buf->b_ffname)
	    buf_ffname = TRUE;
	if (sfname == buf->b_sfname)
	    buf_sfname = TRUE;
	if (fname == buf->b_ffname)
	    buf_fname_f = TRUE;
	if (fname == buf->b_sfname)
	    buf_fname_s = TRUE;

	/* set curwin/curbuf to buf and save a few things */
	aucmd_prepbuf(&aco, buf);
	set_bufref(&bufref, buf);

	if (append)
	{
	    if (!(did_cmd = apply_autocmds_exarg(EVENT_FILEAPPENDCMD,
					 sfname, sfname, FALSE, curbuf, eap)))
	    {
#ifdef FEAT_QUICKFIX
		if (overwriting && bt_nofile(curbuf))
		    nofile_err = TRUE;
		else
#endif
		    apply_autocmds_exarg(EVENT_FILEAPPENDPRE,
					  sfname, sfname, FALSE, curbuf, eap);
	    }
	}
	else if (filtering)
	{
	    apply_autocmds_exarg(EVENT_FILTERWRITEPRE,
					    NULL, sfname, FALSE, curbuf, eap);
	}
	else if (reset_changed && whole)
	{
	    int was_changed = curbufIsChanged();

	    did_cmd = apply_autocmds_exarg(EVENT_BUFWRITECMD,
					  sfname, sfname, FALSE, curbuf, eap);
	    if (did_cmd)
	    {
		if (was_changed && !curbufIsChanged())
		{
		    /* Written everything correctly and BufWriteCmd has reset
		     * 'modified': Correct the undo information so that an
		     * undo now sets 'modified'. */
		    u_unchanged(curbuf);
		    u_update_save_nr(curbuf);
		}
	    }
	    else
	    {
#ifdef FEAT_QUICKFIX
		if (overwriting && bt_nofile(curbuf))
		    nofile_err = TRUE;
		else
#endif
		    apply_autocmds_exarg(EVENT_BUFWRITEPRE,
					  sfname, sfname, FALSE, curbuf, eap);
	    }
	}
	else
	{
	    if (!(did_cmd = apply_autocmds_exarg(EVENT_FILEWRITECMD,
					 sfname, sfname, FALSE, curbuf, eap)))
	    {
#ifdef FEAT_QUICKFIX
		if (overwriting && bt_nofile(curbuf))
		    nofile_err = TRUE;
		else
#endif
		    apply_autocmds_exarg(EVENT_FILEWRITEPRE,
					  sfname, sfname, FALSE, curbuf, eap);
	    }
	}

	/* restore curwin/curbuf and a few other things */
	aucmd_restbuf(&aco);

	/*
	 * In three situations we return here and don't write the file:
	 * 1. the autocommands deleted or unloaded the buffer.
	 * 2. The autocommands abort script processing.
	 * 3. If one of the "Cmd" autocommands was executed.
	 */
	if (!bufref_valid(&bufref))
	    buf = NULL;
	if (buf == NULL || (buf->b_ml.ml_mfp == NULL && !empty_memline)
				       || did_cmd || nofile_err
#ifdef FEAT_EVAL
				       || aborting()
#endif
				       )
	{
	    --no_wait_return;
	    msg_scroll = msg_save;
	    if (nofile_err)
		emsg(_("E676: No matching autocommands for acwrite buffer"));

	    if (nofile_err
#ifdef FEAT_EVAL
		    || aborting()
#endif
		    )
		/* An aborting error, interrupt or exception in the
		 * autocommands. */
		return FAIL;
	    if (did_cmd)
	    {
		if (buf == NULL)
		    /* The buffer was deleted.  We assume it was written
		     * (can't retry anyway). */
		    return OK;
		if (overwriting)
		{
		    /* Assume the buffer was written, update the timestamp. */
		    ml_timestamp(buf);
		    if (append)
			buf->b_flags &= ~BF_NEW;
		    else
			buf->b_flags &= ~BF_WRITE_MASK;
		}
		if (reset_changed && buf->b_changed && !append
			&& (overwriting || vim_strchr(p_cpo, CPO_PLUS) != NULL))
		    /* Buffer still changed, the autocommands didn't work
		     * properly. */
		    return FAIL;
		return OK;
	    }
#ifdef FEAT_EVAL
	    if (!aborting())
#endif
		emsg(_("E203: Autocommands deleted or unloaded buffer to be written"));
	    return FAIL;
	}

	/*
	 * The autocommands may have changed the number of lines in the file.
	 * When writing the whole file, adjust the end.
	 * When writing part of the file, assume that the autocommands only
	 * changed the number of lines that are to be written (tricky!).
	 */
	if (buf->b_ml.ml_line_count != old_line_count)
	{
	    if (whole)						/* write all */
		end = buf->b_ml.ml_line_count;
	    else if (buf->b_ml.ml_line_count > old_line_count)	/* more lines */
		end += buf->b_ml.ml_line_count - old_line_count;
	    else						/* less lines */
	    {
		end -= old_line_count - buf->b_ml.ml_line_count;
		if (end < start)
		{
		    --no_wait_return;
		    msg_scroll = msg_save;
		    emsg(_("E204: Autocommand changed number of lines in unexpected way"));
		    return FAIL;
		}
	    }
	}

	/*
	 * The autocommands may have changed the name of the buffer, which may
	 * be kept in fname, ffname and sfname.
	 */
	if (buf_ffname)
	    ffname = buf->b_ffname;
	if (buf_sfname)
	    sfname = buf->b_sfname;
	if (buf_fname_f)
	    fname = buf->b_ffname;
	if (buf_fname_s)
	    fname = buf->b_sfname;
    }

#ifdef FEAT_NETBEANS_INTG
    if (netbeans_active() && isNetbeansBuffer(buf))
    {
	if (whole)
	{
	    /*
	     * b_changed can be 0 after an undo, but we still need to write
	     * the buffer to NetBeans.
	     */
	    if (buf->b_changed || isNetbeansModified(buf))
	    {
		--no_wait_return;		/* may wait for return now */
		msg_scroll = msg_save;
		netbeans_save_buffer(buf);	/* no error checking... */
		return retval;
	    }
	    else
	    {
		errnum = (char_u *)"E656: ";
		errmsg = (char_u *)_("NetBeans disallows writes of unmodified buffers");
		buffer = NULL;
		goto fail;
	    }
	}
	else
	{
	    errnum = (char_u *)"E657: ";
	    errmsg = (char_u *)_("Partial writes disallowed for NetBeans buffers");
	    buffer = NULL;
	    goto fail;
	}
    }
#endif

    if (shortmess(SHM_OVER) && !exiting)
	msg_scroll = FALSE;	    /* overwrite previous file message */
    else
	msg_scroll = TRUE;	    /* don't overwrite previous file message */
    if (!filtering)
	filemess(buf,
#ifndef UNIX
		sfname,
#else
		fname,
#endif
		    (char_u *)"", 0);	/* show that we are busy */
    msg_scroll = FALSE;		    /* always overwrite the file message now */

    buffer = alloc(BUFSIZE);
    if (buffer == NULL)		    /* can't allocate big buffer, use small
				     * one (to be able to write when out of
				     * memory) */
    {
	buffer = smallbuf;
	bufsize = SMBUFSIZE;
    }
    else
	bufsize = BUFSIZE;

    /*
     * Get information about original file (if there is one).
     */
#if defined(UNIX)
    st_old.st_dev = 0;
    st_old.st_ino = 0;
    perm = -1;
    if (mch_stat((char *)fname, &st_old) < 0)
	newfile = TRUE;
    else
    {
	perm = st_old.st_mode;
	if (!S_ISREG(st_old.st_mode))		/* not a file */
	{
	    if (S_ISDIR(st_old.st_mode))
	    {
		errnum = (char_u *)"E502: ";
		errmsg = (char_u *)_("is a directory");
		goto fail;
	    }
	    if (mch_nodetype(fname) != NODE_WRITABLE)
	    {
		errnum = (char_u *)"E503: ";
		errmsg = (char_u *)_("is not a file or writable device");
		goto fail;
	    }
	    /* It's a device of some kind (or a fifo) which we can write to
	     * but for which we can't make a backup. */
	    device = TRUE;
	    newfile = TRUE;
	    perm = -1;
	}
    }
#else /* !UNIX */
    /*
     * Check for a writable device name.
     */
    c = mch_nodetype(fname);
    if (c == NODE_OTHER)
    {
	errnum = (char_u *)"E503: ";
	errmsg = (char_u *)_("is not a file or writable device");
	goto fail;
    }
    if (c == NODE_WRITABLE)
    {
# if defined(MSWIN)
	/* MS-Windows allows opening a device, but we will probably get stuck
	 * trying to write to it.  */
	if (!p_odev)
	{
	    errnum = (char_u *)"E796: ";
	    errmsg = (char_u *)_("writing to device disabled with 'opendevice' option");
	    goto fail;
	}
# endif
	device = TRUE;
	newfile = TRUE;
	perm = -1;
    }
    else
    {
	perm = mch_getperm(fname);
	if (perm < 0)
	    newfile = TRUE;
	else if (mch_isdir(fname))
	{
	    errnum = (char_u *)"E502: ";
	    errmsg = (char_u *)_("is a directory");
	    goto fail;
	}
	if (overwriting)
	    (void)mch_stat((char *)fname, &st_old);
    }
#endif /* !UNIX */

    if (!device && !newfile)
    {
	/*
	 * Check if the file is really writable (when renaming the file to
	 * make a backup we won't discover it later).
	 */
	file_readonly = check_file_readonly(fname, (int)perm);

	if (!forceit && file_readonly)
	{
	    if (vim_strchr(p_cpo, CPO_FWRITE) != NULL)
	    {
		errnum = (char_u *)"E504: ";
		errmsg = (char_u *)_(err_readonly);
	    }
	    else
	    {
		errnum = (char_u *)"E505: ";
		errmsg = (char_u *)_("is read-only (add ! to override)");
	    }
	    goto fail;
	}

	/*
	 * Check if the timestamp hasn't changed since reading the file.
	 */
	if (overwriting)
	{
	    retval = check_mtime(buf, &st_old);
	    if (retval == FAIL)
		goto fail;
	}
    }

#ifdef HAVE_ACL
    /*
     * For systems that support ACL: get the ACL from the original file.
     */
    if (!newfile)
	acl = mch_get_acl(fname);
#endif

    /*
     * If 'backupskip' is not empty, don't make a backup for some files.
     */
    dobackup = (p_wb || p_bk || *p_pm != NUL);
#ifdef FEAT_WILDIGN
    if (dobackup && *p_bsk != NUL && match_file_list(p_bsk, sfname, ffname))
	dobackup = FALSE;
#endif

    /*
     * Save the value of got_int and reset it.  We don't want a previous
     * interruption cancel writing, only hitting CTRL-C while writing should
     * abort it.
     */
    prev_got_int = got_int;
    got_int = FALSE;

    /* Mark the buffer as 'being saved' to prevent changed buffer warnings */
    buf->b_saving = TRUE;

    /*
     * If we are not appending or filtering, the file exists, and the
     * 'writebackup', 'backup' or 'patchmode' option is set, need a backup.
     * When 'patchmode' is set also make a backup when appending.
     *
     * Do not make any backup, if 'writebackup' and 'backup' are both switched
     * off.  This helps when editing large files on almost-full disks.
     */
    if (!(append && *p_pm == NUL) && !filtering && perm >= 0 && dobackup)
    {
#if defined(UNIX) || defined(MSWIN)
	stat_T	    st;
#endif

	if ((bkc & BKC_YES) || append)	/* "yes" */
	    backup_copy = TRUE;
#if defined(UNIX) || defined(MSWIN)
	else if ((bkc & BKC_AUTO))	/* "auto" */
	{
	    int		i;

# ifdef UNIX
	    /*
	     * Don't rename the file when:
	     * - it's a hard link
	     * - it's a symbolic link
	     * - we don't have write permission in the directory
	     * - we can't set the owner/group of the new file
	     */
	    if (st_old.st_nlink > 1
		    || mch_lstat((char *)fname, &st) < 0
		    || st.st_dev != st_old.st_dev
		    || st.st_ino != st_old.st_ino
#  ifndef HAVE_FCHOWN
		    || st.st_uid != st_old.st_uid
		    || st.st_gid != st_old.st_gid
#  endif
		    )
		backup_copy = TRUE;
	    else
# else
#  ifdef MSWIN
	    /* On NTFS file systems hard links are possible. */
	    if (mch_is_linked(fname))
		backup_copy = TRUE;
	    else
#  endif
# endif
	    {
		/*
		 * Check if we can create a file and set the owner/group to
		 * the ones from the original file.
		 * First find a file name that doesn't exist yet (use some
		 * arbitrary numbers).
		 */
		STRCPY(IObuff, fname);
		for (i = 4913; ; i += 123)
		{
		    sprintf((char *)gettail(IObuff), "%d", i);
		    if (mch_lstat((char *)IObuff, &st) < 0)
			break;
		}
		fd = mch_open((char *)IObuff,
				    O_CREAT|O_WRONLY|O_EXCL|O_NOFOLLOW, perm);
		if (fd < 0)	/* can't write in directory */
		    backup_copy = TRUE;
		else
		{
# ifdef UNIX
#  ifdef HAVE_FCHOWN
		    vim_ignored = fchown(fd, st_old.st_uid, st_old.st_gid);
#  endif
		    if (mch_stat((char *)IObuff, &st) < 0
			    || st.st_uid != st_old.st_uid
			    || st.st_gid != st_old.st_gid
			    || (long)st.st_mode != perm)
			backup_copy = TRUE;
# endif
		    /* Close the file before removing it, on MS-Windows we
		     * can't delete an open file. */
		    close(fd);
		    mch_remove(IObuff);
# ifdef MSWIN
		    /* MS-Windows may trigger a virus scanner to open the
		     * file, we can't delete it then.  Keep trying for half a
		     * second. */
		    {
			int try;

			for (try = 0; try < 10; ++try)
			{
			    if (mch_lstat((char *)IObuff, &st) < 0)
				break;
			    ui_delay(50L, TRUE);  /* wait 50 msec */
			    mch_remove(IObuff);
			}
		    }
# endif
		}
	    }
	}

	/*
	 * Break symlinks and/or hardlinks if we've been asked to.
	 */
	if ((bkc & BKC_BREAKSYMLINK) || (bkc & BKC_BREAKHARDLINK))
	{
# ifdef UNIX
	    int	lstat_res;

	    lstat_res = mch_lstat((char *)fname, &st);

	    /* Symlinks. */
	    if ((bkc & BKC_BREAKSYMLINK)
		    && lstat_res == 0
		    && st.st_ino != st_old.st_ino)
		backup_copy = FALSE;

	    /* Hardlinks. */
	    if ((bkc & BKC_BREAKHARDLINK)
		    && st_old.st_nlink > 1
		    && (lstat_res != 0 || st.st_ino == st_old.st_ino))
		backup_copy = FALSE;
# else
#  if defined(MSWIN)
	    /* Symlinks. */
	    if ((bkc & BKC_BREAKSYMLINK) && mch_is_symbolic_link(fname))
		backup_copy = FALSE;

	    /* Hardlinks. */
	    if ((bkc & BKC_BREAKHARDLINK) && mch_is_hard_link(fname))
		backup_copy = FALSE;
#  endif
# endif
	}

#endif

	/* make sure we have a valid backup extension to use */
	if (*p_bex == NUL)
	    backup_ext = (char_u *)".bak";
	else
	    backup_ext = p_bex;

	if (backup_copy
		&& (fd = mch_open((char *)fname, O_RDONLY | O_EXTRA, 0)) >= 0)
	{
	    int		bfd;
	    char_u	*copybuf, *wp;
	    int		some_error = FALSE;
	    stat_T	st_new;
	    char_u	*dirp;
	    char_u	*rootname;
#if defined(UNIX) || defined(MSWIN)
	    char_u      *p;
#endif
#if defined(UNIX)
	    int		did_set_shortname;
	    mode_t	umask_save;
#endif

	    copybuf = alloc(BUFSIZE + 1);
	    if (copybuf == NULL)
	    {
		some_error = TRUE;	    /* out of memory */
		goto nobackup;
	    }

	    /*
	     * Try to make the backup in each directory in the 'bdir' option.
	     *
	     * Unix semantics has it, that we may have a writable file,
	     * that cannot be recreated with a simple open(..., O_CREAT, ) e.g:
	     *  - the directory is not writable,
	     *  - the file may be a symbolic link,
	     *  - the file may belong to another user/group, etc.
	     *
	     * For these reasons, the existing writable file must be truncated
	     * and reused. Creation of a backup COPY will be attempted.
	     */
	    dirp = p_bdir;
	    while (*dirp)
	    {
#ifdef UNIX
		st_new.st_ino = 0;
		st_new.st_dev = 0;
		st_new.st_gid = 0;
#endif

		/*
		 * Isolate one directory name, using an entry in 'bdir'.
		 */
		(void)copy_option_part(&dirp, copybuf, BUFSIZE, ",");

#if defined(UNIX) || defined(MSWIN)
		p = copybuf + STRLEN(copybuf);
		if (after_pathsep(copybuf, p) && p[-1] == p[-2])
		    // Ends with '//', use full path
		    if ((p = make_percent_swname(copybuf, fname)) != NULL)
		    {
			backup = modname(p, backup_ext, FALSE);
			vim_free(p);
		    }
#endif
		rootname = get_file_in_dir(fname, copybuf);
		if (rootname == NULL)
		{
		    some_error = TRUE;	    /* out of memory */
		    goto nobackup;
		}

#if defined(UNIX)
		did_set_shortname = FALSE;
#endif

		/*
		 * May try twice if 'shortname' not set.
		 */
		for (;;)
		{
		    /*
		     * Make the backup file name.
		     */
		    if (backup == NULL)
			backup = buf_modname((buf->b_p_sn || buf->b_shortname),
						 rootname, backup_ext, FALSE);
		    if (backup == NULL)
		    {
			vim_free(rootname);
			some_error = TRUE;		/* out of memory */
			goto nobackup;
		    }

		    /*
		     * Check if backup file already exists.
		     */
		    if (mch_stat((char *)backup, &st_new) >= 0)
		    {
#ifdef UNIX
			/*
			 * Check if backup file is same as original file.
			 * May happen when modname() gave the same file back.
			 * E.g. silly link, or file name-length reached.
			 * If we don't check here, we either ruin the file
			 * when copying or erase it after writing. jw.
			 */
			if (st_new.st_dev == st_old.st_dev
					    && st_new.st_ino == st_old.st_ino)
			{
			    VIM_CLEAR(backup);	/* no backup file to delete */
			    /*
			     * may try again with 'shortname' set
			     */
			    if (!(buf->b_shortname || buf->b_p_sn))
			    {
				buf->b_shortname = TRUE;
				did_set_shortname = TRUE;
				continue;
			    }
				/* setting shortname didn't help */
			    if (did_set_shortname)
				buf->b_shortname = FALSE;
			    break;
			}
#endif

			/*
			 * If we are not going to keep the backup file, don't
			 * delete an existing one, try to use another name.
			 * Change one character, just before the extension.
			 */
			if (!p_bk)
			{
			    wp = backup + STRLEN(backup) - 1
							 - STRLEN(backup_ext);
			    if (wp < backup)	/* empty file name ??? */
				wp = backup;
			    *wp = 'z';
			    while (*wp > 'a'
				    && mch_stat((char *)backup, &st_new) >= 0)
				--*wp;
			    /* They all exist??? Must be something wrong. */
			    if (*wp == 'a')
				VIM_CLEAR(backup);
			}
		    }
		    break;
		}
		vim_free(rootname);

		/*
		 * Try to create the backup file
		 */
		if (backup != NULL)
		{
		    /* remove old backup, if present */
		    mch_remove(backup);
		    /* Open with O_EXCL to avoid the file being created while
		     * we were sleeping (symlink hacker attack?). Reset umask
		     * if possible to avoid mch_setperm() below. */
#ifdef UNIX
		    umask_save = umask(0);
#endif
		    bfd = mch_open((char *)backup,
				O_WRONLY|O_CREAT|O_EXTRA|O_EXCL|O_NOFOLLOW,
								 perm & 0777);
#ifdef UNIX
		    (void)umask(umask_save);
#endif
		    if (bfd < 0)
			VIM_CLEAR(backup);
		    else
		    {
			/* Set file protection same as original file, but
			 * strip s-bit.  Only needed if umask() wasn't used
			 * above. */
#ifndef UNIX
			(void)mch_setperm(backup, perm & 0777);
#else
			/*
			 * Try to set the group of the backup same as the
			 * original file. If this fails, set the protection
			 * bits for the group same as the protection bits for
			 * others.
			 */
			if (st_new.st_gid != st_old.st_gid
# ifdef HAVE_FCHOWN  /* sequent-ptx lacks fchown() */
				&& fchown(bfd, (uid_t)-1, st_old.st_gid) != 0
# endif
						)
			    mch_setperm(backup,
					  (perm & 0707) | ((perm & 07) << 3));
# if defined(HAVE_SELINUX) || defined(HAVE_SMACK)
			mch_copy_sec(fname, backup);
# endif
#endif

			/*
			 * copy the file.
			 */
			write_info.bw_fd = bfd;
			write_info.bw_buf = copybuf;
#ifdef HAS_BW_FLAGS
			write_info.bw_flags = FIO_NOCONVERT;
#endif
			while ((write_info.bw_len = read_eintr(fd, copybuf,
								BUFSIZE)) > 0)
			{
			    if (buf_write_bytes(&write_info) == FAIL)
			    {
				errmsg = (char_u *)_("E506: Can't write to backup file (add ! to override)");
				break;
			    }
			    ui_breakcheck();
			    if (got_int)
			    {
				errmsg = (char_u *)_(e_interr);
				break;
			    }
			}

			if (close(bfd) < 0 && errmsg == NULL)
			    errmsg = (char_u *)_("E507: Close error for backup file (add ! to override)");
			if (write_info.bw_len < 0)
			    errmsg = (char_u *)_("E508: Can't read file for backup (add ! to override)");
#ifdef UNIX
			set_file_time(backup, st_old.st_atime, st_old.st_mtime);
#endif
#ifdef HAVE_ACL
			mch_set_acl(backup, acl);
#endif
#if defined(HAVE_SELINUX) || defined(HAVE_SMACK)
			mch_copy_sec(fname, backup);
#endif
			break;
		    }
		}
	    }
    nobackup:
	    close(fd);		/* ignore errors for closing read file */
	    vim_free(copybuf);

	    if (backup == NULL && errmsg == NULL)
		errmsg = (char_u *)_("E509: Cannot create backup file (add ! to override)");
	    /* ignore errors when forceit is TRUE */
	    if ((some_error || errmsg != NULL) && !forceit)
	    {
		retval = FAIL;
		goto fail;
	    }
	    errmsg = NULL;
	}
	else
	{
	    char_u	*dirp;
	    char_u	*p;
	    char_u	*rootname;

	    /*
	     * Make a backup by renaming the original file.
	     */
	    /*
	     * If 'cpoptions' includes the "W" flag, we don't want to
	     * overwrite a read-only file.  But rename may be possible
	     * anyway, thus we need an extra check here.
	     */
	    if (file_readonly && vim_strchr(p_cpo, CPO_FWRITE) != NULL)
	    {
		errnum = (char_u *)"E504: ";
		errmsg = (char_u *)_(err_readonly);
		goto fail;
	    }

	    /*
	     *
	     * Form the backup file name - change path/fo.o.h to
	     * path/fo.o.h.bak Try all directories in 'backupdir', first one
	     * that works is used.
	     */
	    dirp = p_bdir;
	    while (*dirp)
	    {
		/*
		 * Isolate one directory name and make the backup file name.
		 */
		(void)copy_option_part(&dirp, IObuff, IOSIZE, ",");

#if defined(UNIX) || defined(MSWIN)
		p = IObuff + STRLEN(IObuff);
		if (after_pathsep(IObuff, p) && p[-1] == p[-2])
		    // path ends with '//', use full path
		    if ((p = make_percent_swname(IObuff, fname)) != NULL)
		    {
			backup = modname(p, backup_ext, FALSE);
			vim_free(p);
		    }
#endif
		if (backup == NULL)
		{
		    rootname = get_file_in_dir(fname, IObuff);
		    if (rootname == NULL)
			backup = NULL;
		    else
		    {
			backup = buf_modname(
				(buf->b_p_sn || buf->b_shortname),
						rootname, backup_ext, FALSE);
			vim_free(rootname);
		    }
		}

		if (backup != NULL)
		{
		    /*
		     * If we are not going to keep the backup file, don't
		     * delete an existing one, try to use another name.
		     * Change one character, just before the extension.
		     */
		    if (!p_bk && mch_getperm(backup) >= 0)
		    {
			p = backup + STRLEN(backup) - 1 - STRLEN(backup_ext);
			if (p < backup)	/* empty file name ??? */
			    p = backup;
			*p = 'z';
			while (*p > 'a' && mch_getperm(backup) >= 0)
			    --*p;
			/* They all exist??? Must be something wrong! */
			if (*p == 'a')
			    VIM_CLEAR(backup);
		    }
		}
		if (backup != NULL)
		{
		    /*
		     * Delete any existing backup and move the current version
		     * to the backup.	For safety, we don't remove the backup
		     * until the write has finished successfully. And if the
		     * 'backup' option is set, leave it around.
		     */
		    /*
		     * If the renaming of the original file to the backup file
		     * works, quit here.
		     */
		    if (vim_rename(fname, backup) == 0)
			break;

		    VIM_CLEAR(backup);   /* don't do the rename below */
		}
	    }
	    if (backup == NULL && !forceit)
	    {
		errmsg = (char_u *)_("E510: Can't make backup file (add ! to override)");
		goto fail;
	    }
	}
    }

#if defined(UNIX)
    /* When using ":w!" and the file was read-only: make it writable */
    if (forceit && perm >= 0 && !(perm & 0200) && st_old.st_uid == getuid()
				     && vim_strchr(p_cpo, CPO_FWRITE) == NULL)
    {
	perm |= 0200;
	(void)mch_setperm(fname, perm);
	made_writable = TRUE;
    }
#endif

    /* When using ":w!" and writing to the current file, 'readonly' makes no
     * sense, reset it, unless 'Z' appears in 'cpoptions'.  */
    if (forceit && overwriting && vim_strchr(p_cpo, CPO_KEEPRO) == NULL)
    {
	buf->b_p_ro = FALSE;
#ifdef FEAT_TITLE
	need_maketitle = TRUE;	    /* set window title later */
#endif
	status_redraw_all();	    /* redraw status lines later */
    }

    if (end > buf->b_ml.ml_line_count)
	end = buf->b_ml.ml_line_count;
    if (buf->b_ml.ml_flags & ML_EMPTY)
	start = end + 1;

    /*
     * If the original file is being overwritten, there is a small chance that
     * we crash in the middle of writing. Therefore the file is preserved now.
     * This makes all block numbers positive so that recovery does not need
     * the original file.
     * Don't do this if there is a backup file and we are exiting.
     */
    if (reset_changed && !newfile && overwriting
					      && !(exiting && backup != NULL))
    {
	ml_preserve(buf, FALSE);
	if (got_int)
	{
	    errmsg = (char_u *)_(e_interr);
	    goto restore_backup;
	}
    }

#ifdef VMS
    vms_remove_version(fname); /* remove version */
#endif
    /* Default: write the file directly.  May write to a temp file for
     * multi-byte conversion. */
    wfname = fname;

    /* Check for forced 'fileencoding' from "++opt=val" argument. */
    if (eap != NULL && eap->force_enc != 0)
    {
	fenc = eap->cmd + eap->force_enc;
	fenc = enc_canonize(fenc);
	fenc_tofree = fenc;
    }
    else
	fenc = buf->b_p_fenc;

    /*
     * Check if the file needs to be converted.
     */
    converted = need_conversion(fenc);

    /*
     * Check if UTF-8 to UCS-2/4 or Latin1 conversion needs to be done.  Or
     * Latin1 to Unicode conversion.  This is handled in buf_write_bytes().
     * Prepare the flags for it and allocate bw_conv_buf when needed.
     */
    if (converted && (enc_utf8 || STRCMP(p_enc, "latin1") == 0))
    {
	wb_flags = get_fio_flags(fenc);
	if (wb_flags & (FIO_UCS2 | FIO_UCS4 | FIO_UTF16 | FIO_UTF8))
	{
	    /* Need to allocate a buffer to translate into. */
	    if (wb_flags & (FIO_UCS2 | FIO_UTF16 | FIO_UTF8))
		write_info.bw_conv_buflen = bufsize * 2;
	    else /* FIO_UCS4 */
		write_info.bw_conv_buflen = bufsize * 4;
	    write_info.bw_conv_buf
			   = lalloc((long_u)write_info.bw_conv_buflen, TRUE);
	    if (write_info.bw_conv_buf == NULL)
		end = 0;
	}
    }

#ifdef MSWIN
    if (converted && wb_flags == 0 && (wb_flags = get_win_fio_flags(fenc)) != 0)
    {
	/* Convert UTF-8 -> UCS-2 and UCS-2 -> DBCS.  Worst-case * 4: */
	write_info.bw_conv_buflen = bufsize * 4;
	write_info.bw_conv_buf
			    = lalloc((long_u)write_info.bw_conv_buflen, TRUE);
	if (write_info.bw_conv_buf == NULL)
	    end = 0;
    }
#endif

#ifdef MACOS_CONVERT
    if (converted && wb_flags == 0 && (wb_flags = get_mac_fio_flags(fenc)) != 0)
    {
	write_info.bw_conv_buflen = bufsize * 3;
	write_info.bw_conv_buf
			    = lalloc((long_u)write_info.bw_conv_buflen, TRUE);
	if (write_info.bw_conv_buf == NULL)
	    end = 0;
    }
#endif

#if defined(FEAT_EVAL) || defined(USE_ICONV)
    if (converted && wb_flags == 0)
    {
# ifdef USE_ICONV
	/*
	 * Use iconv() conversion when conversion is needed and it's not done
	 * internally.
	 */
	write_info.bw_iconv_fd = (iconv_t)my_iconv_open(fenc,
					enc_utf8 ? (char_u *)"utf-8" : p_enc);
	if (write_info.bw_iconv_fd != (iconv_t)-1)
	{
	    /* We're going to use iconv(), allocate a buffer to convert in. */
	    write_info.bw_conv_buflen = bufsize * ICONV_MULT;
	    write_info.bw_conv_buf
			   = lalloc((long_u)write_info.bw_conv_buflen, TRUE);
	    if (write_info.bw_conv_buf == NULL)
		end = 0;
	    write_info.bw_first = TRUE;
	}
#  ifdef FEAT_EVAL
	else
#  endif
# endif

# ifdef FEAT_EVAL
	    /*
	     * When the file needs to be converted with 'charconvert' after
	     * writing, write to a temp file instead and let the conversion
	     * overwrite the original file.
	     */
	    if (*p_ccv != NUL)
	    {
		wfname = vim_tempname('w', FALSE);
		if (wfname == NULL)	/* Can't write without a tempfile! */
		{
		    errmsg = (char_u *)_("E214: Can't find temp file for writing");
		    goto restore_backup;
		}
	    }
# endif
    }
#endif
    if (converted && wb_flags == 0
#ifdef USE_ICONV
	    && write_info.bw_iconv_fd == (iconv_t)-1
# endif
# ifdef FEAT_EVAL
	    && wfname == fname
# endif
	    )
    {
	if (!forceit)
	{
	    errmsg = (char_u *)_("E213: Cannot convert (add ! to write without conversion)");
	    goto restore_backup;
	}
	notconverted = TRUE;
    }

    /*
     * If conversion is taking place, we may first pretend to write and check
     * for conversion errors.  Then loop again to write for real.
     * When not doing conversion this writes for real right away.
     */
    for (checking_conversion = TRUE; ; checking_conversion = FALSE)
    {
	/*
	 * There is no need to check conversion when:
	 * - there is no conversion
	 * - we make a backup file, that can be restored in case of conversion
	 *   failure.
	 */
	if (!converted || dobackup)
	    checking_conversion = FALSE;

	if (checking_conversion)
	{
	    /* Make sure we don't write anything. */
	    fd = -1;
	    write_info.bw_fd = fd;
	}
	else
	{
#ifdef HAVE_FTRUNCATE
# define TRUNC_ON_OPEN 0
#else
# define TRUNC_ON_OPEN O_TRUNC
#endif
	    /*
	     * Open the file "wfname" for writing.
	     * We may try to open the file twice: If we can't write to the file
	     * and forceit is TRUE we delete the existing file and try to
	     * create a new one. If this still fails we may have lost the
	     * original file!  (this may happen when the user reached his
	     * quotum for number of files).
	     * Appending will fail if the file does not exist and forceit is
	     * FALSE.
	     */
	    while ((fd = mch_open((char *)wfname, O_WRONLY | O_EXTRA | (append
				? (forceit ? (O_APPEND | O_CREAT) : O_APPEND)
				: (O_CREAT | TRUNC_ON_OPEN))
				, perm < 0 ? 0666 : (perm & 0777))) < 0)
	    {
		/*
		 * A forced write will try to create a new file if the old one
		 * is still readonly. This may also happen when the directory
		 * is read-only. In that case the mch_remove() will fail.
		 */
		if (errmsg == NULL)
		{
#ifdef UNIX
		    stat_T	st;

		    /* Don't delete the file when it's a hard or symbolic link.
		     */
		    if ((!newfile && st_old.st_nlink > 1)
			    || (mch_lstat((char *)fname, &st) == 0
				&& (st.st_dev != st_old.st_dev
				    || st.st_ino != st_old.st_ino)))
			errmsg = (char_u *)_("E166: Can't open linked file for writing");
		    else
#endif
		    {
			errmsg = (char_u *)_("E212: Can't open file for writing");
			if (forceit && vim_strchr(p_cpo, CPO_FWRITE) == NULL
								  && perm >= 0)
			{
#ifdef UNIX
			    /* we write to the file, thus it should be marked
			       writable after all */
			    if (!(perm & 0200))
				made_writable = TRUE;
			    perm |= 0200;
			    if (st_old.st_uid != getuid()
						  || st_old.st_gid != getgid())
				perm &= 0777;
#endif
			    if (!append)  /* don't remove when appending */
				mch_remove(wfname);
			    continue;
			}
		    }
		}

restore_backup:
		{
		    stat_T	st;

		    /*
		     * If we failed to open the file, we don't need a backup.
		     * Throw it away.  If we moved or removed the original file
		     * try to put the backup in its place.
		     */
		    if (backup != NULL && wfname == fname)
		    {
			if (backup_copy)
			{
			    /*
			     * There is a small chance that we removed the
			     * original, try to move the copy in its place.
			     * This may not work if the vim_rename() fails.
			     * In that case we leave the copy around.
			     */
			    /* If file does not exist, put the copy in its
			     * place */
			    if (mch_stat((char *)fname, &st) < 0)
				vim_rename(backup, fname);
			    /* if original file does exist throw away the copy
			     */
			    if (mch_stat((char *)fname, &st) >= 0)
				mch_remove(backup);
			}
			else
			{
			    /* try to put the original file back */
			    vim_rename(backup, fname);
			}
		    }

		    /* if original file no longer exists give an extra warning
		     */
		    if (!newfile && mch_stat((char *)fname, &st) < 0)
			end = 0;
		}

		if (wfname != fname)
		    vim_free(wfname);
		goto fail;
	    }
	    write_info.bw_fd = fd;

#if defined(UNIX)
	    {
		stat_T	st;

		/* Double check we are writing the intended file before making
		 * any changes. */
		if (overwriting
			&& (!dobackup || backup_copy)
			&& fname == wfname
			&& perm >= 0
			&& mch_fstat(fd, &st) == 0
			&& st.st_ino != st_old.st_ino)
		{
		    close(fd);
		    errmsg = (char_u *)_("E949: File changed while writing");
		    goto fail;
		}
	    }
#endif
#ifdef HAVE_FTRUNCATE
	    if (!append)
		vim_ignored = ftruncate(fd, (off_t)0);
#endif

#if defined(MSWIN)
	    if (backup != NULL && overwriting && !append)
	    {
		if (backup_copy)
		    (void)mch_copy_file_attribute(wfname, backup);
		else
		    (void)mch_copy_file_attribute(backup, wfname);
	    }

	    if (!overwriting && !append)
	    {
		if (buf->b_ffname != NULL)
		    (void)mch_copy_file_attribute(buf->b_ffname, wfname);
		/* Should copy resource fork */
	    }
#endif

#ifdef FEAT_CRYPT
	    if (*buf->b_p_key != NUL && !filtering)
	    {
		char_u		*header;
		int		header_len;

		buf->b_cryptstate = crypt_create_for_writing(
						      crypt_get_method_nr(buf),
					   buf->b_p_key, &header, &header_len);
		if (buf->b_cryptstate == NULL || header == NULL)
		    end = 0;
		else
		{
		    /* Write magic number, so that Vim knows how this file is
		     * encrypted when reading it back. */
		    write_info.bw_buf = header;
		    write_info.bw_len = header_len;
		    write_info.bw_flags = FIO_NOCONVERT;
		    if (buf_write_bytes(&write_info) == FAIL)
			end = 0;
		    wb_flags |= FIO_ENCRYPTED;
		    vim_free(header);
		}
	    }
#endif
	}
	errmsg = NULL;

	write_info.bw_buf = buffer;
	nchars = 0;

	/* use "++bin", "++nobin" or 'binary' */
	if (eap != NULL && eap->force_bin != 0)
	    write_bin = (eap->force_bin == FORCE_BIN);
	else
	    write_bin = buf->b_p_bin;

	/*
	 * The BOM is written just after the encryption magic number.
	 * Skip it when appending and the file already existed, the BOM only
	 * makes sense at the start of the file.
	 */
	if (buf->b_p_bomb && !write_bin && (!append || perm < 0))
	{
	    write_info.bw_len = make_bom(buffer, fenc);
	    if (write_info.bw_len > 0)
	    {
		/* don't convert, do encryption */
		write_info.bw_flags = FIO_NOCONVERT | wb_flags;
		if (buf_write_bytes(&write_info) == FAIL)
		    end = 0;
		else
		    nchars += write_info.bw_len;
	    }
	}
	write_info.bw_start_lnum = start;

#ifdef FEAT_PERSISTENT_UNDO
	write_undo_file = (buf->b_p_udf
			    && overwriting
			    && !append
			    && !filtering
			    && reset_changed
			    && !checking_conversion);
	if (write_undo_file)
	    /* Prepare for computing the hash value of the text. */
	    sha256_start(&sha_ctx);
#endif

	write_info.bw_len = bufsize;
#ifdef HAS_BW_FLAGS
	write_info.bw_flags = wb_flags;
#endif
	fileformat = get_fileformat_force(buf, eap);
	s = buffer;
	len = 0;
	for (lnum = start; lnum <= end; ++lnum)
	{
	    /*
	     * The next while loop is done once for each character written.
	     * Keep it fast!
	     */
	    ptr = ml_get_buf(buf, lnum, FALSE) - 1;
#ifdef FEAT_PERSISTENT_UNDO
	    if (write_undo_file)
		sha256_update(&sha_ctx, ptr + 1,
					      (UINT32_T)(STRLEN(ptr + 1) + 1));
#endif
	    while ((c = *++ptr) != NUL)
	    {
		if (c == NL)
		    *s = NUL;		/* replace newlines with NULs */
		else if (c == CAR && fileformat == EOL_MAC)
		    *s = NL;		/* Mac: replace CRs with NLs */
		else
		    *s = c;
		++s;
		if (++len != bufsize)
		    continue;
		if (buf_write_bytes(&write_info) == FAIL)
		{
		    end = 0;		/* write error: break loop */
		    break;
		}
		nchars += bufsize;
		s = buffer;
		len = 0;
		write_info.bw_start_lnum = lnum;
	    }
	    /* write failed or last line has no EOL: stop here */
	    if (end == 0
		    || (lnum == end
			&& (write_bin || !buf->b_p_fixeol)
			&& (lnum == buf->b_no_eol_lnum
			    || (lnum == buf->b_ml.ml_line_count
							   && !buf->b_p_eol))))
	    {
		++lnum;			/* written the line, count it */
		no_eol = TRUE;
		break;
	    }
	    if (fileformat == EOL_UNIX)
		*s++ = NL;
	    else
	    {
		*s++ = CAR;		    /* EOL_MAC or EOL_DOS: write CR */
		if (fileformat == EOL_DOS)  /* write CR-NL */
		{
		    if (++len == bufsize)
		    {
			if (buf_write_bytes(&write_info) == FAIL)
			{
			    end = 0;	/* write error: break loop */
			    break;
			}
			nchars += bufsize;
			s = buffer;
			len = 0;
		    }
		    *s++ = NL;
		}
	    }
	    if (++len == bufsize && end)
	    {
		if (buf_write_bytes(&write_info) == FAIL)
		{
		    end = 0;		/* write error: break loop */
		    break;
		}
		nchars += bufsize;
		s = buffer;
		len = 0;

		ui_breakcheck();
		if (got_int)
		{
		    end = 0;		/* Interrupted, break loop */
		    break;
		}
	    }
#ifdef VMS
	    /*
	     * On VMS there is a problem: newlines get added when writing
	     * blocks at a time. Fix it by writing a line at a time.
	     * This is much slower!
	     * Explanation: VAX/DECC RTL insists that records in some RMS
	     * structures end with a newline (carriage return) character, and
	     * if they don't it adds one.
	     * With other RMS structures it works perfect without this fix.
	     */
	    if (buf->b_fab_rfm == FAB$C_VFC
		    || ((buf->b_fab_rat & (FAB$M_FTN | FAB$M_CR)) != 0))
	    {
		int b2write;

		buf->b_fab_mrs = (buf->b_fab_mrs == 0
			? MIN(4096, bufsize)
			: MIN(buf->b_fab_mrs, bufsize));

		b2write = len;
		while (b2write > 0)
		{
		    write_info.bw_len = MIN(b2write, buf->b_fab_mrs);
		    if (buf_write_bytes(&write_info) == FAIL)
		    {
			end = 0;
			break;
		    }
		    b2write -= MIN(b2write, buf->b_fab_mrs);
		}
		write_info.bw_len = bufsize;
		nchars += len;
		s = buffer;
		len = 0;
	    }
#endif
	}
	if (len > 0 && end > 0)
	{
	    write_info.bw_len = len;
	    if (buf_write_bytes(&write_info) == FAIL)
		end = 0;		    /* write error */
	    nchars += len;
	}

	/* Stop when writing done or an error was encountered. */
	if (!checking_conversion || end == 0)
	    break;

	/* If no error happened until now, writing should be ok, so loop to
	 * really write the buffer. */
    }

    /* If we started writing, finish writing. Also when an error was
     * encountered. */
    if (!checking_conversion)
    {
#if defined(UNIX) && defined(HAVE_FSYNC)
	/*
	 * On many journalling file systems there is a bug that causes both the
	 * original and the backup file to be lost when halting the system
	 * right after writing the file.  That's because only the meta-data is
	 * journalled.  Syncing the file slows down the system, but assures it
	 * has been written to disk and we don't lose it.
	 * For a device do try the fsync() but don't complain if it does not
	 * work (could be a pipe).
	 * If the 'fsync' option is FALSE, don't fsync().  Useful for laptops.
	 */
	if (p_fs && vim_fsync(fd) != 0 && !device)
	{
	    errmsg = (char_u *)_(e_fsync);
	    end = 0;
	}
#endif

#if defined(HAVE_SELINUX) || defined(HAVE_SMACK)
	/* Probably need to set the security context. */
	if (!backup_copy)
	    mch_copy_sec(backup, wfname);
#endif

#ifdef UNIX
	/* When creating a new file, set its owner/group to that of the
	 * original file.  Get the new device and inode number. */
	if (backup != NULL && !backup_copy)
	{
# ifdef HAVE_FCHOWN
	    stat_T	st;

	    /* Don't change the owner when it's already OK, some systems remove
	     * permission or ACL stuff. */
	    if (mch_stat((char *)wfname, &st) < 0
		    || st.st_uid != st_old.st_uid
		    || st.st_gid != st_old.st_gid)
	    {
		/* changing owner might not be possible */
		vim_ignored = fchown(fd, st_old.st_uid, -1);
		/* if changing group fails clear the group permissions */
		if (fchown(fd, -1, st_old.st_gid) == -1 && perm > 0)
		    perm &= ~070;
	    }
# endif
	    buf_setino(buf);
	}
	else if (!buf->b_dev_valid)
	    /* Set the inode when creating a new file. */
	    buf_setino(buf);
#endif

#ifdef UNIX
	if (made_writable)
	    perm &= ~0200;	/* reset 'w' bit for security reasons */
#endif
#ifdef HAVE_FCHMOD
	/* set permission of new file same as old file */
	if (perm >= 0)
	    (void)mch_fsetperm(fd, perm);
#endif
	if (close(fd) != 0)
	{
	    errmsg = (char_u *)_("E512: Close failed");
	    end = 0;
	}

#ifndef HAVE_FCHMOD
	/* set permission of new file same as old file */
	if (perm >= 0)
	    (void)mch_setperm(wfname, perm);
#endif
#ifdef HAVE_ACL
	/*
	 * Probably need to set the ACL before changing the user (can't set the
	 * ACL on a file the user doesn't own).
	 * On Solaris, with ZFS and the aclmode property set to "discard" (the
	 * default), chmod() discards all part of a file's ACL that don't
	 * represent the mode of the file.  It's non-trivial for us to discover
	 * whether we're in that situation, so we simply always re-set the ACL.
	 */
# ifndef HAVE_SOLARIS_ZFS_ACL
	if (!backup_copy)
# endif
	    mch_set_acl(wfname, acl);
#endif
#ifdef FEAT_CRYPT
	if (buf->b_cryptstate != NULL)
	{
	    crypt_free_state(buf->b_cryptstate);
	    buf->b_cryptstate = NULL;
	}
#endif

#if defined(FEAT_EVAL)
	if (wfname != fname)
	{
	    /*
	     * The file was written to a temp file, now it needs to be
	     * converted with 'charconvert' to (overwrite) the output file.
	     */
	    if (end != 0)
	    {
		if (eval_charconvert(enc_utf8 ? (char_u *)"utf-8" : p_enc,
						  fenc, wfname, fname) == FAIL)
		{
		    write_info.bw_conv_error = TRUE;
		    end = 0;
		}
	    }
	    mch_remove(wfname);
	    vim_free(wfname);
	}
#endif
    }

    if (end == 0)
    {
	/*
	 * Error encountered.
	 */
	if (errmsg == NULL)
	{
	    if (write_info.bw_conv_error)
	    {
		if (write_info.bw_conv_error_lnum == 0)
		    errmsg = (char_u *)_("E513: write error, conversion failed (make 'fenc' empty to override)");
		else
		{
		    errmsg_allocated = TRUE;
		    errmsg = alloc(300);
		    vim_snprintf((char *)errmsg, 300, _("E513: write error, conversion failed in line %ld (make 'fenc' empty to override)"),
					 (long)write_info.bw_conv_error_lnum);
		}
	    }
	    else if (got_int)
		errmsg = (char_u *)_(e_interr);
	    else
		errmsg = (char_u *)_("E514: write error (file system full?)");
	}

	/*
	 * If we have a backup file, try to put it in place of the new file,
	 * because the new file is probably corrupt.  This avoids losing the
	 * original file when trying to make a backup when writing the file a
	 * second time.
	 * When "backup_copy" is set we need to copy the backup over the new
	 * file.  Otherwise rename the backup file.
	 * If this is OK, don't give the extra warning message.
	 */
	if (backup != NULL)
	{
	    if (backup_copy)
	    {
		/* This may take a while, if we were interrupted let the user
		 * know we got the message. */
		if (got_int)
		{
		    msg(_(e_interr));
		    out_flush();
		}
		if ((fd = mch_open((char *)backup, O_RDONLY | O_EXTRA, 0)) >= 0)
		{
		    if ((write_info.bw_fd = mch_open((char *)fname,
				    O_WRONLY | O_CREAT | O_TRUNC | O_EXTRA,
							   perm & 0777)) >= 0)
		    {
			/* copy the file. */
			write_info.bw_buf = smallbuf;
#ifdef HAS_BW_FLAGS
			write_info.bw_flags = FIO_NOCONVERT;
#endif
			while ((write_info.bw_len = read_eintr(fd, smallbuf,
						      SMBUFSIZE)) > 0)
			    if (buf_write_bytes(&write_info) == FAIL)
				break;

			if (close(write_info.bw_fd) >= 0
						   && write_info.bw_len == 0)
			    end = 1;		/* success */
		    }
		    close(fd);	/* ignore errors for closing read file */
		}
	    }
	    else
	    {
		if (vim_rename(backup, fname) == 0)
		    end = 1;
	    }
	}
	goto fail;
    }

    lnum -= start;	    /* compute number of written lines */
    --no_wait_return;	    /* may wait for return now */

#if !(defined(UNIX) || defined(VMS))
    fname = sfname;	    /* use shortname now, for the messages */
#endif
    if (!filtering)
    {
	msg_add_fname(buf, fname);	/* put fname in IObuff with quotes */
	c = FALSE;
	if (write_info.bw_conv_error)
	{
	    STRCAT(IObuff, _(" CONVERSION ERROR"));
	    c = TRUE;
	    if (write_info.bw_conv_error_lnum != 0)
		vim_snprintf_add((char *)IObuff, IOSIZE, _(" in line %ld;"),
			(long)write_info.bw_conv_error_lnum);
	}
	else if (notconverted)
	{
	    STRCAT(IObuff, _("[NOT converted]"));
	    c = TRUE;
	}
	else if (converted)
	{
	    STRCAT(IObuff, _("[converted]"));
	    c = TRUE;
	}
	if (device)
	{
	    STRCAT(IObuff, _("[Device]"));
	    c = TRUE;
	}
	else if (newfile)
	{
	    STRCAT(IObuff, shortmess(SHM_NEW) ? _("[New]") : _("[New File]"));
	    c = TRUE;
	}
	if (no_eol)
	{
	    msg_add_eol();
	    c = TRUE;
	}
	/* may add [unix/dos/mac] */
	if (msg_add_fileformat(fileformat))
	    c = TRUE;
#ifdef FEAT_CRYPT
	if (wb_flags & FIO_ENCRYPTED)
	{
	    crypt_append_msg(buf);
	    c = TRUE;
	}
#endif
	msg_add_lines(c, (long)lnum, nchars);	/* add line/char count */
	if (!shortmess(SHM_WRITE))
	{
	    if (append)
		STRCAT(IObuff, shortmess(SHM_WRI) ? _(" [a]") : _(" appended"));
	    else
		STRCAT(IObuff, shortmess(SHM_WRI) ? _(" [w]") : _(" written"));
	}

	set_keep_msg((char_u *)msg_trunc_attr((char *)IObuff, FALSE, 0), 0);
    }

    /* When written everything correctly: reset 'modified'.  Unless not
     * writing to the original file and '+' is not in 'cpoptions'. */
    if (reset_changed && whole && !append
	    && !write_info.bw_conv_error
	    && (overwriting || vim_strchr(p_cpo, CPO_PLUS) != NULL))
    {
	unchanged(buf, TRUE);
	/* b:changedtick is always incremented in unchanged() but that
	 * should not trigger a TextChanged event. */
	if (buf->b_last_changedtick + 1 == CHANGEDTICK(buf))
	    buf->b_last_changedtick = CHANGEDTICK(buf);
	u_unchanged(buf);
	u_update_save_nr(buf);
    }

    /*
     * If written to the current file, update the timestamp of the swap file
     * and reset the BF_WRITE_MASK flags. Also sets buf->b_mtime.
     */
    if (overwriting)
    {
	ml_timestamp(buf);
	if (append)
	    buf->b_flags &= ~BF_NEW;
	else
	    buf->b_flags &= ~BF_WRITE_MASK;
    }

    /*
     * If we kept a backup until now, and we are in patch mode, then we make
     * the backup file our 'original' file.
     */
    if (*p_pm && dobackup)
    {
	char *org = (char *)buf_modname((buf->b_p_sn || buf->b_shortname),
							  fname, p_pm, FALSE);

	if (backup != NULL)
	{
	    stat_T	st;

	    /*
	     * If the original file does not exist yet
	     * the current backup file becomes the original file
	     */
	    if (org == NULL)
		emsg(_("E205: Patchmode: can't save original file"));
	    else if (mch_stat(org, &st) < 0)
	    {
		vim_rename(backup, (char_u *)org);
		VIM_CLEAR(backup);	    /* don't delete the file */
#ifdef UNIX
		set_file_time((char_u *)org, st_old.st_atime, st_old.st_mtime);
#endif
	    }
	}
	/*
	 * If there is no backup file, remember that a (new) file was
	 * created.
	 */
	else
	{
	    int empty_fd;

	    if (org == NULL
		    || (empty_fd = mch_open(org,
				      O_CREAT | O_EXTRA | O_EXCL | O_NOFOLLOW,
					perm < 0 ? 0666 : (perm & 0777))) < 0)
	      emsg(_("E206: patchmode: can't touch empty original file"));
	    else
	      close(empty_fd);
	}
	if (org != NULL)
	{
	    mch_setperm((char_u *)org, mch_getperm(fname) & 0777);
	    vim_free(org);
	}
    }

    /*
     * Remove the backup unless 'backup' option is set
     */
    if (!p_bk && backup != NULL && mch_remove(backup) != 0)
	emsg(_("E207: Can't delete backup file"));

    goto nofail;

    /*
     * Finish up.  We get here either after failure or success.
     */
fail:
    --no_wait_return;		/* may wait for return now */
nofail:

    /* Done saving, we accept changed buffer warnings again */
    buf->b_saving = FALSE;

    vim_free(backup);
    if (buffer != smallbuf)
	vim_free(buffer);
    vim_free(fenc_tofree);
    vim_free(write_info.bw_conv_buf);
#ifdef USE_ICONV
    if (write_info.bw_iconv_fd != (iconv_t)-1)
    {
	iconv_close(write_info.bw_iconv_fd);
	write_info.bw_iconv_fd = (iconv_t)-1;
    }
#endif
#ifdef HAVE_ACL
    mch_free_acl(acl);
#endif

    if (errmsg != NULL)
    {
	int numlen = errnum != NULL ? (int)STRLEN(errnum) : 0;

	attr = HL_ATTR(HLF_E);	/* set highlight for error messages */
	msg_add_fname(buf,
#ifndef UNIX
		sfname
#else
		fname
#endif
		     );		/* put file name in IObuff with quotes */
	if (STRLEN(IObuff) + STRLEN(errmsg) + numlen >= IOSIZE)
	    IObuff[IOSIZE - STRLEN(errmsg) - numlen - 1] = NUL;
	/* If the error message has the form "is ...", put the error number in
	 * front of the file name. */
	if (errnum != NULL)
	{
	    STRMOVE(IObuff + numlen, IObuff);
	    mch_memmove(IObuff, errnum, (size_t)numlen);
	}
	STRCAT(IObuff, errmsg);
	emsg((char *)IObuff);
	if (errmsg_allocated)
	    vim_free(errmsg);

	retval = FAIL;
	if (end == 0)
	{
	    msg_puts_attr(_("\nWARNING: Original file may be lost or damaged\n"),
		    attr | MSG_HIST);
	    msg_puts_attr(_("don't quit the editor until the file is successfully written!"),
		    attr | MSG_HIST);

	    /* Update the timestamp to avoid an "overwrite changed file"
	     * prompt when writing again. */
	    if (mch_stat((char *)fname, &st_old) >= 0)
	    {
		buf_store_time(buf, &st_old, fname);
		buf->b_mtime_read = buf->b_mtime;
	    }
	}
    }
    msg_scroll = msg_save;

#ifdef FEAT_PERSISTENT_UNDO
    /*
     * When writing the whole file and 'undofile' is set, also write the undo
     * file.
     */
    if (retval == OK && write_undo_file)
    {
	char_u	    hash[UNDO_HASH_SIZE];

	sha256_finish(&sha_ctx, hash);
	u_write_undo(NULL, FALSE, buf, hash);
    }
#endif

#ifdef FEAT_EVAL
    if (!should_abort(retval))
#else
    if (!got_int)
#endif
    {
	aco_save_T	aco;

	curbuf->b_no_eol_lnum = 0;  /* in case it was set by the previous read */

	/*
	 * Apply POST autocommands.
	 * Careful: The autocommands may call buf_write() recursively!
	 */
	aucmd_prepbuf(&aco, buf);

	if (append)
	    apply_autocmds_exarg(EVENT_FILEAPPENDPOST, fname, fname,
							  FALSE, curbuf, eap);
	else if (filtering)
	    apply_autocmds_exarg(EVENT_FILTERWRITEPOST, NULL, fname,
							  FALSE, curbuf, eap);
	else if (reset_changed && whole)
	    apply_autocmds_exarg(EVENT_BUFWRITEPOST, fname, fname,
							  FALSE, curbuf, eap);
	else
	    apply_autocmds_exarg(EVENT_FILEWRITEPOST, fname, fname,
							  FALSE, curbuf, eap);

	/* restore curwin/curbuf and a few other things */
	aucmd_restbuf(&aco);

#ifdef FEAT_EVAL
	if (aborting())	    /* autocmds may abort script processing */
	    retval = FALSE;
#endif
    }

    got_int |= prev_got_int;

    return retval;
}

#if defined(HAVE_FSYNC) || defined(PROTO)
/*
 * Call fsync() with Mac-specific exception.
 * Return fsync() result: zero for success.
 */
    int
vim_fsync(int fd)
{
    int r;

# ifdef MACOS_X
    r = fcntl(fd, F_FULLFSYNC);
    if (r != 0)  // F_FULLFSYNC not working or not supported
# endif
	r = fsync(fd);
    return r;
}
#endif

/*
 * Set the name of the current buffer.  Use when the buffer doesn't have a
 * name and a ":r" or ":w" command with a file name is used.
 */
    static int
set_rw_fname(char_u *fname, char_u *sfname)
{
    buf_T	*buf = curbuf;

    /* It's like the unnamed buffer is deleted.... */
    if (curbuf->b_p_bl)
	apply_autocmds(EVENT_BUFDELETE, NULL, NULL, FALSE, curbuf);
    apply_autocmds(EVENT_BUFWIPEOUT, NULL, NULL, FALSE, curbuf);
#ifdef FEAT_EVAL
    if (aborting())	    /* autocmds may abort script processing */
	return FAIL;
#endif
    if (curbuf != buf)
    {
	/* We are in another buffer now, don't do the renaming. */
	emsg(_(e_auchangedbuf));
	return FAIL;
    }

    if (setfname(curbuf, fname, sfname, FALSE) == OK)
	curbuf->b_flags |= BF_NOTEDITED;

    /* ....and a new named one is created */
    apply_autocmds(EVENT_BUFNEW, NULL, NULL, FALSE, curbuf);
    if (curbuf->b_p_bl)
	apply_autocmds(EVENT_BUFADD, NULL, NULL, FALSE, curbuf);
#ifdef FEAT_EVAL
    if (aborting())	    /* autocmds may abort script processing */
	return FAIL;
#endif

    /* Do filetype detection now if 'filetype' is empty. */
    if (*curbuf->b_p_ft == NUL)
    {
	if (au_has_group((char_u *)"filetypedetect"))
	    (void)do_doautocmd((char_u *)"filetypedetect BufRead", FALSE, NULL);
	do_modelines(0);
    }

    return OK;
}

/*
 * Put file name into IObuff with quotes.
 */
    void
msg_add_fname(buf_T *buf, char_u *fname)
{
    if (fname == NULL)
	fname = (char_u *)"-stdin-";
    home_replace(buf, fname, IObuff + 1, IOSIZE - 4, TRUE);
    IObuff[0] = '"';
    STRCAT(IObuff, "\" ");
}

/*
 * Append message for text mode to IObuff.
 * Return TRUE if something appended.
 */
    static int
msg_add_fileformat(int eol_type)
{
#ifndef USE_CRNL
    if (eol_type == EOL_DOS)
    {
	STRCAT(IObuff, shortmess(SHM_TEXT) ? _("[dos]") : _("[dos format]"));
	return TRUE;
    }
#endif
    if (eol_type == EOL_MAC)
    {
	STRCAT(IObuff, shortmess(SHM_TEXT) ? _("[mac]") : _("[mac format]"));
	return TRUE;
    }
#ifdef USE_CRNL
    if (eol_type == EOL_UNIX)
    {
	STRCAT(IObuff, shortmess(SHM_TEXT) ? _("[unix]") : _("[unix format]"));
	return TRUE;
    }
#endif
    return FALSE;
}

/*
 * Append line and character count to IObuff.
 */
    void
msg_add_lines(
    int	    insert_space,
    long    lnum,
    off_T   nchars)
{
    char_u  *p;

    p = IObuff + STRLEN(IObuff);

    if (insert_space)
	*p++ = ' ';
    if (shortmess(SHM_LINES))
	vim_snprintf((char *)p, IOSIZE - (p - IObuff),
		"%ldL, %lldC", lnum, (long_long_T)nchars);
    else
    {
	sprintf((char *)p, NGETTEXT("%ld line, ", "%ld lines, ", lnum), lnum);
	p += STRLEN(p);
	vim_snprintf((char *)p, IOSIZE - (p - IObuff),
		NGETTEXT("%lld character", "%lld characters", nchars),
		(long_long_T)nchars);
    }
}

/*
 * Append message for missing line separator to IObuff.
 */
    static void
msg_add_eol(void)
{
    STRCAT(IObuff, shortmess(SHM_LAST) ? _("[noeol]") : _("[Incomplete last line]"));
}

/*
 * Check modification time of file, before writing to it.
 * The size isn't checked, because using a tool like "gzip" takes care of
 * using the same timestamp but can't set the size.
 */
    static int
check_mtime(buf_T *buf, stat_T *st)
{
    if (buf->b_mtime_read != 0
	    && time_differs((long)st->st_mtime, buf->b_mtime_read))
    {
	msg_scroll = TRUE;	    /* don't overwrite messages here */
	msg_silent = 0;		    /* must give this prompt */
	/* don't use emsg() here, don't want to flush the buffers */
	msg_attr(_("WARNING: The file has been changed since reading it!!!"),
						       HL_ATTR(HLF_E));
	if (ask_yesno((char_u *)_("Do you really want to write to it"),
								 TRUE) == 'n')
	    return FAIL;
	msg_scroll = FALSE;	    /* always overwrite the file message now */
    }
    return OK;
}

    static int
time_differs(long t1, long t2)
{
#if defined(__linux__) || defined(MSWIN)
    /* On a FAT filesystem, esp. under Linux, there are only 5 bits to store
     * the seconds.  Since the roundoff is done when flushing the inode, the
     * time may change unexpectedly by one second!!! */
    return (t1 - t2 > 1 || t2 - t1 > 1);
#else
    return (t1 != t2);
#endif
}

/*
 * Call write() to write a number of bytes to the file.
 * Handles encryption and 'encoding' conversion.
 *
 * Return FAIL for failure, OK otherwise.
 */
    static int
buf_write_bytes(struct bw_info *ip)
{
    int		wlen;
    char_u	*buf = ip->bw_buf;	/* data to write */
    int		len = ip->bw_len;	/* length of data */
#ifdef HAS_BW_FLAGS
    int		flags = ip->bw_flags;	/* extra flags */
#endif

    /*
     * Skip conversion when writing the crypt magic number or the BOM.
     */
    if (!(flags & FIO_NOCONVERT))
    {
	char_u		*p;
	unsigned	c;
	int		n;

	if (flags & FIO_UTF8)
	{
	    /*
	     * Convert latin1 in the buffer to UTF-8 in the file.
	     */
	    p = ip->bw_conv_buf;	/* translate to buffer */
	    for (wlen = 0; wlen < len; ++wlen)
		p += utf_char2bytes(buf[wlen], p);
	    buf = ip->bw_conv_buf;
	    len = (int)(p - ip->bw_conv_buf);
	}
	else if (flags & (FIO_UCS4 | FIO_UTF16 | FIO_UCS2 | FIO_LATIN1))
	{
	    /*
	     * Convert UTF-8 bytes in the buffer to UCS-2, UCS-4, UTF-16 or
	     * Latin1 chars in the file.
	     */
	    if (flags & FIO_LATIN1)
		p = buf;	/* translate in-place (can only get shorter) */
	    else
		p = ip->bw_conv_buf;	/* translate to buffer */
	    for (wlen = 0; wlen < len; wlen += n)
	    {
		if (wlen == 0 && ip->bw_restlen != 0)
		{
		    int		l;

		    /* Use remainder of previous call.  Append the start of
		     * buf[] to get a full sequence.  Might still be too
		     * short! */
		    l = CONV_RESTLEN - ip->bw_restlen;
		    if (l > len)
			l = len;
		    mch_memmove(ip->bw_rest + ip->bw_restlen, buf, (size_t)l);
		    n = utf_ptr2len_len(ip->bw_rest, ip->bw_restlen + l);
		    if (n > ip->bw_restlen + len)
		    {
			/* We have an incomplete byte sequence at the end to
			 * be written.  We can't convert it without the
			 * remaining bytes.  Keep them for the next call. */
			if (ip->bw_restlen + len > CONV_RESTLEN)
			    return FAIL;
			ip->bw_restlen += len;
			break;
		    }
		    if (n > 1)
			c = utf_ptr2char(ip->bw_rest);
		    else
			c = ip->bw_rest[0];
		    if (n >= ip->bw_restlen)
		    {
			n -= ip->bw_restlen;
			ip->bw_restlen = 0;
		    }
		    else
		    {
			ip->bw_restlen -= n;
			mch_memmove(ip->bw_rest, ip->bw_rest + n,
						      (size_t)ip->bw_restlen);
			n = 0;
		    }
		}
		else
		{
		    n = utf_ptr2len_len(buf + wlen, len - wlen);
		    if (n > len - wlen)
		    {
			/* We have an incomplete byte sequence at the end to
			 * be written.  We can't convert it without the
			 * remaining bytes.  Keep them for the next call. */
			if (len - wlen > CONV_RESTLEN)
			    return FAIL;
			ip->bw_restlen = len - wlen;
			mch_memmove(ip->bw_rest, buf + wlen,
						      (size_t)ip->bw_restlen);
			break;
		    }
		    if (n > 1)
			c = utf_ptr2char(buf + wlen);
		    else
			c = buf[wlen];
		}

		if (ucs2bytes(c, &p, flags) && !ip->bw_conv_error)
		{
		    ip->bw_conv_error = TRUE;
		    ip->bw_conv_error_lnum = ip->bw_start_lnum;
		}
		if (c == NL)
		    ++ip->bw_start_lnum;
	    }
	    if (flags & FIO_LATIN1)
		len = (int)(p - buf);
	    else
	    {
		buf = ip->bw_conv_buf;
		len = (int)(p - ip->bw_conv_buf);
	    }
	}

#ifdef MSWIN
	else if (flags & FIO_CODEPAGE)
	{
	    /*
	     * Convert UTF-8 or codepage to UCS-2 and then to MS-Windows
	     * codepage.
	     */
	    char_u	*from;
	    size_t	fromlen;
	    char_u	*to;
	    int		u8c;
	    BOOL	bad = FALSE;
	    int		needed;

	    if (ip->bw_restlen > 0)
	    {
		/* Need to concatenate the remainder of the previous call and
		 * the bytes of the current call.  Use the end of the
		 * conversion buffer for this. */
		fromlen = len + ip->bw_restlen;
		from = ip->bw_conv_buf + ip->bw_conv_buflen - fromlen;
		mch_memmove(from, ip->bw_rest, (size_t)ip->bw_restlen);
		mch_memmove(from + ip->bw_restlen, buf, (size_t)len);
	    }
	    else
	    {
		from = buf;
		fromlen = len;
	    }

	    to = ip->bw_conv_buf;
	    if (enc_utf8)
	    {
		/* Convert from UTF-8 to UCS-2, to the start of the buffer.
		 * The buffer has been allocated to be big enough. */
		while (fromlen > 0)
		{
		    n = (int)utf_ptr2len_len(from, (int)fromlen);
		    if (n > (int)fromlen)	/* incomplete byte sequence */
			break;
		    u8c = utf_ptr2char(from);
		    *to++ = (u8c & 0xff);
		    *to++ = (u8c >> 8);
		    fromlen -= n;
		    from += n;
		}

		/* Copy remainder to ip->bw_rest[] to be used for the next
		 * call. */
		if (fromlen > CONV_RESTLEN)
		{
		    /* weird overlong sequence */
		    ip->bw_conv_error = TRUE;
		    return FAIL;
		}
		mch_memmove(ip->bw_rest, from, fromlen);
		ip->bw_restlen = (int)fromlen;
	    }
	    else
	    {
		/* Convert from enc_codepage to UCS-2, to the start of the
		 * buffer.  The buffer has been allocated to be big enough. */
		ip->bw_restlen = 0;
		needed = MultiByteToWideChar(enc_codepage,
			     MB_ERR_INVALID_CHARS, (LPCSTR)from, (int)fromlen,
								     NULL, 0);
		if (needed == 0)
		{
		    /* When conversion fails there may be a trailing byte. */
		    needed = MultiByteToWideChar(enc_codepage,
			 MB_ERR_INVALID_CHARS, (LPCSTR)from, (int)fromlen - 1,
								     NULL, 0);
		    if (needed == 0)
		    {
			/* Conversion doesn't work. */
			ip->bw_conv_error = TRUE;
			return FAIL;
		    }
		    /* Save the trailing byte for the next call. */
		    ip->bw_rest[0] = from[fromlen - 1];
		    ip->bw_restlen = 1;
		}
		needed = MultiByteToWideChar(enc_codepage, MB_ERR_INVALID_CHARS,
				(LPCSTR)from, (int)(fromlen - ip->bw_restlen),
							  (LPWSTR)to, needed);
		if (needed == 0)
		{
		    /* Safety check: Conversion doesn't work. */
		    ip->bw_conv_error = TRUE;
		    return FAIL;
		}
		to += needed * 2;
	    }

	    fromlen = to - ip->bw_conv_buf;
	    buf = to;
# ifdef CP_UTF8	/* VC 4.1 doesn't define CP_UTF8 */
	    if (FIO_GET_CP(flags) == CP_UTF8)
	    {
		/* Convert from UCS-2 to UTF-8, using the remainder of the
		 * conversion buffer.  Fails when out of space. */
		for (from = ip->bw_conv_buf; fromlen > 1; fromlen -= 2)
		{
		    u8c = *from++;
		    u8c += (*from++ << 8);
		    to += utf_char2bytes(u8c, to);
		    if (to + 6 >= ip->bw_conv_buf + ip->bw_conv_buflen)
		    {
			ip->bw_conv_error = TRUE;
			return FAIL;
		    }
		}
		len = (int)(to - buf);
	    }
	    else
# endif
	    {
		/* Convert from UCS-2 to the codepage, using the remainder of
		 * the conversion buffer.  If the conversion uses the default
		 * character "0", the data doesn't fit in this encoding, so
		 * fail. */
		len = WideCharToMultiByte(FIO_GET_CP(flags), 0,
			(LPCWSTR)ip->bw_conv_buf, (int)fromlen / sizeof(WCHAR),
			(LPSTR)to, (int)(ip->bw_conv_buflen - fromlen), 0,
									&bad);
		if (bad)
		{
		    ip->bw_conv_error = TRUE;
		    return FAIL;
		}
	    }
	}
#endif

#ifdef MACOS_CONVERT
	else if (flags & FIO_MACROMAN)
	{
	    /*
	     * Convert UTF-8 or latin1 to Apple MacRoman.
	     */
	    char_u	*from;
	    size_t	fromlen;

	    if (ip->bw_restlen > 0)
	    {
		/* Need to concatenate the remainder of the previous call and
		 * the bytes of the current call.  Use the end of the
		 * conversion buffer for this. */
		fromlen = len + ip->bw_restlen;
		from = ip->bw_conv_buf + ip->bw_conv_buflen - fromlen;
		mch_memmove(from, ip->bw_rest, (size_t)ip->bw_restlen);
		mch_memmove(from + ip->bw_restlen, buf, (size_t)len);
	    }
	    else
	    {
		from = buf;
		fromlen = len;
	    }

	    if (enc2macroman(from, fromlen,
			ip->bw_conv_buf, &len, ip->bw_conv_buflen,
			ip->bw_rest, &ip->bw_restlen) == FAIL)
	    {
		ip->bw_conv_error = TRUE;
		return FAIL;
	    }
	    buf = ip->bw_conv_buf;
	}
#endif

#ifdef USE_ICONV
	if (ip->bw_iconv_fd != (iconv_t)-1)
	{
	    const char	*from;
	    size_t	fromlen;
	    char	*to;
	    size_t	tolen;

	    /* Convert with iconv(). */
	    if (ip->bw_restlen > 0)
	    {
		char *fp;

		/* Need to concatenate the remainder of the previous call and
		 * the bytes of the current call.  Use the end of the
		 * conversion buffer for this. */
		fromlen = len + ip->bw_restlen;
		fp = (char *)ip->bw_conv_buf + ip->bw_conv_buflen - fromlen;
		mch_memmove(fp, ip->bw_rest, (size_t)ip->bw_restlen);
		mch_memmove(fp + ip->bw_restlen, buf, (size_t)len);
		from = fp;
		tolen = ip->bw_conv_buflen - fromlen;
	    }
	    else
	    {
		from = (const char *)buf;
		fromlen = len;
		tolen = ip->bw_conv_buflen;
	    }
	    to = (char *)ip->bw_conv_buf;

	    if (ip->bw_first)
	    {
		size_t	save_len = tolen;

		/* output the initial shift state sequence */
		(void)iconv(ip->bw_iconv_fd, NULL, NULL, &to, &tolen);

		/* There is a bug in iconv() on Linux (which appears to be
		 * wide-spread) which sets "to" to NULL and messes up "tolen".
		 */
		if (to == NULL)
		{
		    to = (char *)ip->bw_conv_buf;
		    tolen = save_len;
		}
		ip->bw_first = FALSE;
	    }

	    /*
	     * If iconv() has an error or there is not enough room, fail.
	     */
	    if ((iconv(ip->bw_iconv_fd, (void *)&from, &fromlen, &to, &tolen)
			== (size_t)-1 && ICONV_ERRNO != ICONV_EINVAL)
						    || fromlen > CONV_RESTLEN)
	    {
		ip->bw_conv_error = TRUE;
		return FAIL;
	    }

	    /* copy remainder to ip->bw_rest[] to be used for the next call. */
	    if (fromlen > 0)
		mch_memmove(ip->bw_rest, (void *)from, fromlen);
	    ip->bw_restlen = (int)fromlen;

	    buf = ip->bw_conv_buf;
	    len = (int)((char_u *)to - ip->bw_conv_buf);
	}
#endif
    }

    if (ip->bw_fd < 0)
	/* Only checking conversion, which is OK if we get here. */
	return OK;

#ifdef FEAT_CRYPT
    if (flags & FIO_ENCRYPTED)
    {
	/* Encrypt the data. Do it in-place if possible, otherwise use an
	 * allocated buffer. */
# ifdef CRYPT_NOT_INPLACE
	if (crypt_works_inplace(ip->bw_buffer->b_cryptstate))
	{
# endif
	    crypt_encode_inplace(ip->bw_buffer->b_cryptstate, buf, len);
# ifdef CRYPT_NOT_INPLACE
	}
	else
	{
	    char_u *outbuf;

	    len = crypt_encode_alloc(curbuf->b_cryptstate, buf, len, &outbuf);
	    if (len == 0)
		return OK;  /* Crypt layer is buffering, will flush later. */
	    wlen = write_eintr(ip->bw_fd, outbuf, len);
	    vim_free(outbuf);
	    return (wlen < len) ? FAIL : OK;
	}
# endif
    }
#endif

    wlen = write_eintr(ip->bw_fd, buf, len);
    return (wlen < len) ? FAIL : OK;
}

/*
 * Convert a Unicode character to bytes.
 * Return TRUE for an error, FALSE when it's OK.
 */
    static int
ucs2bytes(
    unsigned	c,		/* in: character */
    char_u	**pp,		/* in/out: pointer to result */
    int		flags)		/* FIO_ flags */
{
    char_u	*p = *pp;
    int		error = FALSE;
    int		cc;


    if (flags & FIO_UCS4)
    {
	if (flags & FIO_ENDIAN_L)
	{
	    *p++ = c;
	    *p++ = (c >> 8);
	    *p++ = (c >> 16);
	    *p++ = (c >> 24);
	}
	else
	{
	    *p++ = (c >> 24);
	    *p++ = (c >> 16);
	    *p++ = (c >> 8);
	    *p++ = c;
	}
    }
    else if (flags & (FIO_UCS2 | FIO_UTF16))
    {
	if (c >= 0x10000)
	{
	    if (flags & FIO_UTF16)
	    {
		/* Make two words, ten bits of the character in each.  First
		 * word is 0xd800 - 0xdbff, second one 0xdc00 - 0xdfff */
		c -= 0x10000;
		if (c >= 0x100000)
		    error = TRUE;
		cc = ((c >> 10) & 0x3ff) + 0xd800;
		if (flags & FIO_ENDIAN_L)
		{
		    *p++ = cc;
		    *p++ = ((unsigned)cc >> 8);
		}
		else
		{
		    *p++ = ((unsigned)cc >> 8);
		    *p++ = cc;
		}
		c = (c & 0x3ff) + 0xdc00;
	    }
	    else
		error = TRUE;
	}
	if (flags & FIO_ENDIAN_L)
	{
	    *p++ = c;
	    *p++ = (c >> 8);
	}
	else
	{
	    *p++ = (c >> 8);
	    *p++ = c;
	}
    }
    else    /* Latin1 */
    {
	if (c >= 0x100)
	{
	    error = TRUE;
	    *p++ = 0xBF;
	}
	else
	    *p++ = c;
    }

    *pp = p;
    return error;
}

/*
 * Return TRUE if file encoding "fenc" requires conversion from or to
 * 'encoding'.
 */
    static int
need_conversion(char_u *fenc)
{
    int		same_encoding;
    int		enc_flags;
    int		fenc_flags;

    if (*fenc == NUL || STRCMP(p_enc, fenc) == 0)
    {
	same_encoding = TRUE;
	fenc_flags = 0;
    }
    else
    {
	/* Ignore difference between "ansi" and "latin1", "ucs-4" and
	 * "ucs-4be", etc. */
	enc_flags = get_fio_flags(p_enc);
	fenc_flags = get_fio_flags(fenc);
	same_encoding = (enc_flags != 0 && fenc_flags == enc_flags);
    }
    if (same_encoding)
    {
	/* Specified encoding matches with 'encoding'.  This requires
	 * conversion when 'encoding' is Unicode but not UTF-8. */
	return enc_unicode != 0;
    }

    /* Encodings differ.  However, conversion is not needed when 'enc' is any
     * Unicode encoding and the file is UTF-8. */
    return !(enc_utf8 && fenc_flags == FIO_UTF8);
}

/*
 * Check "ptr" for a unicode encoding and return the FIO_ flags needed for the
 * internal conversion.
 * if "ptr" is an empty string, use 'encoding'.
 */
    static int
get_fio_flags(char_u *ptr)
{
    int		prop;

    if (*ptr == NUL)
	ptr = p_enc;

    prop = enc_canon_props(ptr);
    if (prop & ENC_UNICODE)
    {
	if (prop & ENC_2BYTE)
	{
	    if (prop & ENC_ENDIAN_L)
		return FIO_UCS2 | FIO_ENDIAN_L;
	    return FIO_UCS2;
	}
	if (prop & ENC_4BYTE)
	{
	    if (prop & ENC_ENDIAN_L)
		return FIO_UCS4 | FIO_ENDIAN_L;
	    return FIO_UCS4;
	}
	if (prop & ENC_2WORD)
	{
	    if (prop & ENC_ENDIAN_L)
		return FIO_UTF16 | FIO_ENDIAN_L;
	    return FIO_UTF16;
	}
	return FIO_UTF8;
    }
    if (prop & ENC_LATIN1)
	return FIO_LATIN1;
    /* must be ENC_DBCS, requires iconv() */
    return 0;
}

#ifdef MSWIN
/*
 * Check "ptr" for a MS-Windows codepage name and return the FIO_ flags needed
 * for the conversion MS-Windows can do for us.  Also accept "utf-8".
 * Used for conversion between 'encoding' and 'fileencoding'.
 */
    static int
get_win_fio_flags(char_u *ptr)
{
    int		cp;

    /* Cannot do this when 'encoding' is not utf-8 and not a codepage. */
    if (!enc_utf8 && enc_codepage <= 0)
	return 0;

    cp = encname2codepage(ptr);
    if (cp == 0)
    {
#  ifdef CP_UTF8	/* VC 4.1 doesn't define CP_UTF8 */
	if (STRCMP(ptr, "utf-8") == 0)
	    cp = CP_UTF8;
	else
#  endif
	    return 0;
    }
    return FIO_PUT_CP(cp) | FIO_CODEPAGE;
}
#endif

#ifdef MACOS_CONVERT
/*
 * Check "ptr" for a Carbon supported encoding and return the FIO_ flags
 * needed for the internal conversion to/from utf-8 or latin1.
 */
    static int
get_mac_fio_flags(char_u *ptr)
{
    if ((enc_utf8 || STRCMP(p_enc, "latin1") == 0)
				     && (enc_canon_props(ptr) & ENC_MACROMAN))
	return FIO_MACROMAN;
    return 0;
}
#endif

/*
 * Check for a Unicode BOM (Byte Order Mark) at the start of p[size].
 * "size" must be at least 2.
 * Return the name of the encoding and set "*lenp" to the length.
 * Returns NULL when no BOM found.
 */
    static char_u *
check_for_bom(
    char_u	*p,
    long	size,
    int		*lenp,
    int		flags)
{
    char	*name = NULL;
    int		len = 2;

    if (p[0] == 0xef && p[1] == 0xbb && size >= 3 && p[2] == 0xbf
	    && (flags == FIO_ALL || flags == FIO_UTF8 || flags == 0))
    {
	name = "utf-8";		/* EF BB BF */
	len = 3;
    }
    else if (p[0] == 0xff && p[1] == 0xfe)
    {
	if (size >= 4 && p[2] == 0 && p[3] == 0
	    && (flags == FIO_ALL || flags == (FIO_UCS4 | FIO_ENDIAN_L)))
	{
	    name = "ucs-4le";	/* FF FE 00 00 */
	    len = 4;
	}
	else if (flags == (FIO_UCS2 | FIO_ENDIAN_L))
	    name = "ucs-2le";	/* FF FE */
	else if (flags == FIO_ALL || flags == (FIO_UTF16 | FIO_ENDIAN_L))
	    /* utf-16le is preferred, it also works for ucs-2le text */
	    name = "utf-16le";	/* FF FE */
    }
    else if (p[0] == 0xfe && p[1] == 0xff
	    && (flags == FIO_ALL || flags == FIO_UCS2 || flags == FIO_UTF16))
    {
	/* Default to utf-16, it works also for ucs-2 text. */
	if (flags == FIO_UCS2)
	    name = "ucs-2";	/* FE FF */
	else
	    name = "utf-16";	/* FE FF */
    }
    else if (size >= 4 && p[0] == 0 && p[1] == 0 && p[2] == 0xfe
	    && p[3] == 0xff && (flags == FIO_ALL || flags == FIO_UCS4))
    {
	name = "ucs-4";		/* 00 00 FE FF */
	len = 4;
    }

    *lenp = len;
    return (char_u *)name;
}

/*
 * Generate a BOM in "buf[4]" for encoding "name".
 * Return the length of the BOM (zero when no BOM).
 */
    static int
make_bom(char_u *buf, char_u *name)
{
    int		flags;
    char_u	*p;

    flags = get_fio_flags(name);

    /* Can't put a BOM in a non-Unicode file. */
    if (flags == FIO_LATIN1 || flags == 0)
	return 0;

    if (flags == FIO_UTF8)	/* UTF-8 */
    {
	buf[0] = 0xef;
	buf[1] = 0xbb;
	buf[2] = 0xbf;
	return 3;
    }
    p = buf;
    (void)ucs2bytes(0xfeff, &p, flags);
    return (int)(p - buf);
}

/*
 * Try to find a shortname by comparing the fullname with the current
 * directory.
 * Returns "full_path" or pointer into "full_path" if shortened.
 */
    char_u *
shorten_fname1(char_u *full_path)
{
    char_u	*dirname;
    char_u	*p = full_path;

    dirname = alloc(MAXPATHL);
    if (dirname == NULL)
	return full_path;
    if (mch_dirname(dirname, MAXPATHL) == OK)
    {
	p = shorten_fname(full_path, dirname);
	if (p == NULL || *p == NUL)
	    p = full_path;
    }
    vim_free(dirname);
    return p;
}

/*
 * Try to find a shortname by comparing the fullname with the current
 * directory.
 * Returns NULL if not shorter name possible, pointer into "full_path"
 * otherwise.
 */
    char_u *
shorten_fname(char_u *full_path, char_u *dir_name)
{
    int		len;
    char_u	*p;

    if (full_path == NULL)
	return NULL;
    len = (int)STRLEN(dir_name);
    if (fnamencmp(dir_name, full_path, len) == 0)
    {
	p = full_path + len;
#if defined(MSWIN)
	/*
	 * MS-Windows: when a file is in the root directory, dir_name will end
	 * in a slash, since C: by itself does not define a specific dir. In
	 * this case p may already be correct. <negri>
	 */
	if (!((len > 2) && (*(p - 2) == ':')))
#endif
	{
	    if (vim_ispathsep(*p))
		++p;
#ifndef VMS   /* the path separator is always part of the path */
	    else
		p = NULL;
#endif
	}
    }
#if defined(MSWIN)
    /*
     * When using a file in the current drive, remove the drive name:
     * "A:\dir\file" -> "\dir\file".  This helps when moving a session file on
     * a floppy from "A:\dir" to "B:\dir".
     */
    else if (len > 3
	    && TOUPPER_LOC(full_path[0]) == TOUPPER_LOC(dir_name[0])
	    && full_path[1] == ':'
	    && vim_ispathsep(full_path[2]))
	p = full_path + 2;
#endif
    else
	p = NULL;
    return p;
}

/*
 * Shorten filename of a buffer.
 * When "force" is TRUE: Use full path from now on for files currently being
 * edited, both for file name and swap file name.  Try to shorten the file
 * names a bit, if safe to do so.
 * When "force" is FALSE: Only try to shorten absolute file names.
 * For buffers that have buftype "nofile" or "scratch": never change the file
 * name.
 */
    void
shorten_buf_fname(buf_T *buf, char_u *dirname, int force)
{
    char_u	*p;

    if (buf->b_fname != NULL
#ifdef FEAT_QUICKFIX
	    && !bt_nofile(buf)
#endif
	    && !path_with_url(buf->b_fname)
	    && (force
		|| buf->b_sfname == NULL
		|| mch_isFullName(buf->b_sfname)))
    {
	if (buf->b_sfname != buf->b_ffname)
	    VIM_CLEAR(buf->b_sfname);
	p = shorten_fname(buf->b_ffname, dirname);
	if (p != NULL)
	{
	    buf->b_sfname = vim_strsave(p);
	    buf->b_fname = buf->b_sfname;
	}
	if (p == NULL || buf->b_fname == NULL)
	    buf->b_fname = buf->b_ffname;
    }
}

/*
 * Shorten filenames for all buffers.
 */
    void
shorten_fnames(int force)
{
    char_u	dirname[MAXPATHL];
    buf_T	*buf;

    mch_dirname(dirname, MAXPATHL);
    FOR_ALL_BUFFERS(buf)
    {
	shorten_buf_fname(buf, dirname, force);

	/* Always make the swap file name a full path, a "nofile" buffer may
	 * also have a swap file. */
	mf_fullname(buf->b_ml.ml_mfp);
    }
    status_redraw_all();
    redraw_tabline = TRUE;
}

#if (defined(FEAT_DND) && defined(FEAT_GUI_GTK)) \
	|| defined(FEAT_GUI_MSWIN) \
	|| defined(FEAT_GUI_MAC) \
	|| defined(PROTO)
/*
 * Shorten all filenames in "fnames[count]" by current directory.
 */
    void
shorten_filenames(char_u **fnames, int count)
{
    int		i;
    char_u	dirname[MAXPATHL];
    char_u	*p;

    if (fnames == NULL || count < 1)
	return;
    mch_dirname(dirname, sizeof(dirname));
    for (i = 0; i < count; ++i)
    {
	if ((p = shorten_fname(fnames[i], dirname)) != NULL)
	{
	    /* shorten_fname() returns pointer in given "fnames[i]".  If free
	     * "fnames[i]" first, "p" becomes invalid.  So we need to copy
	     * "p" first then free fnames[i]. */
	    p = vim_strsave(p);
	    vim_free(fnames[i]);
	    fnames[i] = p;
	}
    }
}
#endif

/*
 * Add extension to file name - change path/fo.o.h to path/fo.o.h.ext or
 * fo_o_h.ext for MSDOS or when shortname option set.
 *
 * Assumed that fname is a valid name found in the filesystem we assure that
 * the return value is a different name and ends in 'ext'.
 * "ext" MUST be at most 4 characters long if it starts with a dot, 3
 * characters otherwise.
 * Space for the returned name is allocated, must be freed later.
 * Returns NULL when out of memory.
 */
    char_u *
modname(
    char_u *fname,
    char_u *ext,
    int	    prepend_dot)	/* may prepend a '.' to file name */
{
    return buf_modname((curbuf->b_p_sn || curbuf->b_shortname),
						     fname, ext, prepend_dot);
}

    char_u *
buf_modname(
    int	    shortname,		/* use 8.3 file name */
    char_u  *fname,
    char_u  *ext,
    int	    prepend_dot)	/* may prepend a '.' to file name */
{
    char_u	*retval;
    char_u	*s;
    char_u	*e;
    char_u	*ptr;
    int		fnamelen, extlen;

    extlen = (int)STRLEN(ext);

    /*
     * If there is no file name we must get the name of the current directory
     * (we need the full path in case :cd is used).
     */
    if (fname == NULL || *fname == NUL)
    {
	retval = alloc((unsigned)(MAXPATHL + extlen + 3));
	if (retval == NULL)
	    return NULL;
	if (mch_dirname(retval, MAXPATHL) == FAIL ||
				     (fnamelen = (int)STRLEN(retval)) == 0)
	{
	    vim_free(retval);
	    return NULL;
	}
	if (!after_pathsep(retval, retval + fnamelen))
	{
	    retval[fnamelen++] = PATHSEP;
	    retval[fnamelen] = NUL;
	}
	prepend_dot = FALSE;	    /* nothing to prepend a dot to */
    }
    else
    {
	fnamelen = (int)STRLEN(fname);
	retval = alloc((unsigned)(fnamelen + extlen + 3));
	if (retval == NULL)
	    return NULL;
	STRCPY(retval, fname);
#ifdef VMS
	vms_remove_version(retval); /* we do not need versions here */
#endif
    }

    /*
     * search backwards until we hit a '/', '\' or ':' replacing all '.'
     * by '_' for MSDOS or when shortname option set and ext starts with a dot.
     * Then truncate what is after the '/', '\' or ':' to 8 characters for
     * MSDOS and 26 characters for AMIGA, a lot more for UNIX.
     */
    for (ptr = retval + fnamelen; ptr > retval; MB_PTR_BACK(retval, ptr))
    {
	if (*ext == '.' && shortname)
	    if (*ptr == '.')	/* replace '.' by '_' */
		*ptr = '_';
	if (vim_ispathsep(*ptr))
	{
	    ++ptr;
	    break;
	}
    }

    /* the file name has at most BASENAMELEN characters. */
    if (STRLEN(ptr) > (unsigned)BASENAMELEN)
	ptr[BASENAMELEN] = '\0';

    s = ptr + STRLEN(ptr);

    /*
     * For 8.3 file names we may have to reduce the length.
     */
    if (shortname)
    {
	/*
	 * If there is no file name, or the file name ends in '/', and the
	 * extension starts with '.', put a '_' before the dot, because just
	 * ".ext" is invalid.
	 */
	if (fname == NULL || *fname == NUL
				   || vim_ispathsep(fname[STRLEN(fname) - 1]))
	{
	    if (*ext == '.')
		*s++ = '_';
	}
	/*
	 * If the extension starts with '.', truncate the base name at 8
	 * characters
	 */
	else if (*ext == '.')
	{
	    if ((size_t)(s - ptr) > (size_t)8)
	    {
		s = ptr + 8;
		*s = '\0';
	    }
	}
	/*
	 * If the extension doesn't start with '.', and the file name
	 * doesn't have an extension yet, append a '.'
	 */
	else if ((e = vim_strchr(ptr, '.')) == NULL)
	    *s++ = '.';
	/*
	 * If the extension doesn't start with '.', and there already is an
	 * extension, it may need to be truncated
	 */
	else if ((int)STRLEN(e) + extlen > 4)
	    s = e + 4 - extlen;
    }
#ifdef MSWIN
    /*
     * If there is no file name, and the extension starts with '.', put a
     * '_' before the dot, because just ".ext" may be invalid if it's on a
     * FAT partition, and on HPFS it doesn't matter.
     */
    else if ((fname == NULL || *fname == NUL) && *ext == '.')
	*s++ = '_';
#endif

    /*
     * Append the extension.
     * ext can start with '.' and cannot exceed 3 more characters.
     */
    STRCPY(s, ext);

    /*
     * Prepend the dot.
     */
    if (prepend_dot && !shortname && *(e = gettail(retval)) != '.')
    {
	STRMOVE(e + 1, e);
	*e = '.';
    }

    /*
     * Check that, after appending the extension, the file name is really
     * different.
     */
    if (fname != NULL && STRCMP(fname, retval) == 0)
    {
	/* we search for a character that can be replaced by '_' */
	while (--s >= ptr)
	{
	    if (*s != '_')
	    {
		*s = '_';
		break;
	    }
	}
	if (s < ptr)	/* fname was "________.<ext>", how tricky! */
	    *ptr = 'v';
    }
    return retval;
}

/*
 * Like fgets(), but if the file line is too long, it is truncated and the
 * rest of the line is thrown away.  Returns TRUE for end-of-file.
 * If the line is truncated then buf[size - 2] will not be NUL.
 */
    int
vim_fgets(char_u *buf, int size, FILE *fp)
{
    char	*eof;
#define FGETS_SIZE 200
    char	tbuf[FGETS_SIZE];

    buf[size - 2] = NUL;
    eof = fgets((char *)buf, size, fp);
    if (buf[size - 2] != NUL && buf[size - 2] != '\n')
    {
	buf[size - 1] = NUL;	    /* Truncate the line */

	/* Now throw away the rest of the line: */
	do
	{
	    tbuf[FGETS_SIZE - 2] = NUL;
	    vim_ignoredp = fgets((char *)tbuf, FGETS_SIZE, fp);
	} while (tbuf[FGETS_SIZE - 2] != NUL && tbuf[FGETS_SIZE - 2] != '\n');
    }
    return (eof == NULL);
}

/*
 * rename() only works if both files are on the same file system, this
 * function will (attempts to?) copy the file across if rename fails -- webb
 * Return -1 for failure, 0 for success.
 */
    int
vim_rename(char_u *from, char_u *to)
{
    int		fd_in;
    int		fd_out;
    int		n;
    char	*errmsg = NULL;
    char	*buffer;
#ifdef AMIGA
    BPTR	flock;
#endif
    stat_T	st;
    long	perm;
#ifdef HAVE_ACL
    vim_acl_T	acl;		/* ACL from original file */
#endif
    int		use_tmp_file = FALSE;

    /*
     * When the names are identical, there is nothing to do.  When they refer
     * to the same file (ignoring case and slash/backslash differences) but
     * the file name differs we need to go through a temp file.
     */
    if (fnamecmp(from, to) == 0)
    {
	if (p_fic && STRCMP(gettail(from), gettail(to)) != 0)
	    use_tmp_file = TRUE;
	else
	    return 0;
    }

    /*
     * Fail if the "from" file doesn't exist.  Avoids that "to" is deleted.
     */
    if (mch_stat((char *)from, &st) < 0)
	return -1;

#ifdef UNIX
    {
	stat_T	st_to;

	/* It's possible for the source and destination to be the same file.
	 * This happens when "from" and "to" differ in case and are on a FAT32
	 * filesystem.  In that case go through a temp file name. */
	if (mch_stat((char *)to, &st_to) >= 0
		&& st.st_dev == st_to.st_dev
		&& st.st_ino == st_to.st_ino)
	    use_tmp_file = TRUE;
    }
#endif
#ifdef MSWIN
    {
	BY_HANDLE_FILE_INFORMATION info1, info2;

	/* It's possible for the source and destination to be the same file.
	 * In that case go through a temp file name.  This makes rename("foo",
	 * "./foo") a no-op (in a complicated way). */
	if (win32_fileinfo(from, &info1) == FILEINFO_OK
		&& win32_fileinfo(to, &info2) == FILEINFO_OK
		&& info1.dwVolumeSerialNumber == info2.dwVolumeSerialNumber
		&& info1.nFileIndexHigh == info2.nFileIndexHigh
		&& info1.nFileIndexLow == info2.nFileIndexLow)
	    use_tmp_file = TRUE;
    }
#endif

    if (use_tmp_file)
    {
	char	tempname[MAXPATHL + 1];

	/*
	 * Find a name that doesn't exist and is in the same directory.
	 * Rename "from" to "tempname" and then rename "tempname" to "to".
	 */
	if (STRLEN(from) >= MAXPATHL - 5)
	    return -1;
	STRCPY(tempname, from);
	for (n = 123; n < 99999; ++n)
	{
	    sprintf((char *)gettail((char_u *)tempname), "%d", n);
	    if (mch_stat(tempname, &st) < 0)
	    {
		if (mch_rename((char *)from, tempname) == 0)
		{
		    if (mch_rename(tempname, (char *)to) == 0)
			return 0;
		    /* Strange, the second step failed.  Try moving the
		     * file back and return failure. */
		    mch_rename(tempname, (char *)from);
		    return -1;
		}
		/* If it fails for one temp name it will most likely fail
		 * for any temp name, give up. */
		return -1;
	    }
	}
	return -1;
    }

    /*
     * Delete the "to" file, this is required on some systems to make the
     * mch_rename() work, on other systems it makes sure that we don't have
     * two files when the mch_rename() fails.
     */

#ifdef AMIGA
    /*
     * With MSDOS-compatible filesystems (crossdos, messydos) it is possible
     * that the name of the "to" file is the same as the "from" file, even
     * though the names are different. To avoid the chance of accidentally
     * deleting the "from" file (horror!) we lock it during the remove.
     *
     * When used for making a backup before writing the file: This should not
     * happen with ":w", because startscript() should detect this problem and
     * set buf->b_shortname, causing modname() to return a correct ".bak" file
     * name.  This problem does exist with ":w filename", but then the
     * original file will be somewhere else so the backup isn't really
     * important. If autoscripting is off the rename may fail.
     */
    flock = Lock((UBYTE *)from, (long)ACCESS_READ);
#endif
    mch_remove(to);
#ifdef AMIGA
    if (flock)
	UnLock(flock);
#endif

    /*
     * First try a normal rename, return if it works.
     */
    if (mch_rename((char *)from, (char *)to) == 0)
	return 0;

    /*
     * Rename() failed, try copying the file.
     */
    perm = mch_getperm(from);
#ifdef HAVE_ACL
    /* For systems that support ACL: get the ACL from the original file. */
    acl = mch_get_acl(from);
#endif
    fd_in = mch_open((char *)from, O_RDONLY|O_EXTRA, 0);
    if (fd_in == -1)
    {
#ifdef HAVE_ACL
	mch_free_acl(acl);
#endif
	return -1;
    }

    /* Create the new file with same permissions as the original. */
    fd_out = mch_open((char *)to,
		       O_CREAT|O_EXCL|O_WRONLY|O_EXTRA|O_NOFOLLOW, (int)perm);
    if (fd_out == -1)
    {
	close(fd_in);
#ifdef HAVE_ACL
	mch_free_acl(acl);
#endif
	return -1;
    }

    buffer = (char *)alloc(BUFSIZE);
    if (buffer == NULL)
    {
	close(fd_out);
	close(fd_in);
#ifdef HAVE_ACL
	mch_free_acl(acl);
#endif
	return -1;
    }

    while ((n = read_eintr(fd_in, buffer, BUFSIZE)) > 0)
	if (write_eintr(fd_out, buffer, n) != n)
	{
	    errmsg = _("E208: Error writing to \"%s\"");
	    break;
	}

    vim_free(buffer);
    close(fd_in);
    if (close(fd_out) < 0)
	errmsg = _("E209: Error closing \"%s\"");
    if (n < 0)
    {
	errmsg = _("E210: Error reading \"%s\"");
	to = from;
    }
#ifndef UNIX	    /* for Unix mch_open() already set the permission */
    mch_setperm(to, perm);
#endif
#ifdef HAVE_ACL
    mch_set_acl(to, acl);
    mch_free_acl(acl);
#endif
#if defined(HAVE_SELINUX) || defined(HAVE_SMACK)
    mch_copy_sec(from, to);
#endif
    if (errmsg != NULL)
    {
	semsg(errmsg, to);
	return -1;
    }
    mch_remove(from);
    return 0;
}

static int already_warned = FALSE;

/*
 * Check if any not hidden buffer has been changed.
 * Postpone the check if there are characters in the stuff buffer, a global
 * command is being executed, a mapping is being executed or an autocommand is
 * busy.
 * Returns TRUE if some message was written (screen should be redrawn and
 * cursor positioned).
 */
    int
check_timestamps(
    int		focus)		/* called for GUI focus event */
{
    buf_T	*buf;
    int		didit = 0;
    int		n;

    /* Don't check timestamps while system() or another low-level function may
     * cause us to lose and gain focus. */
    if (no_check_timestamps > 0)
	return FALSE;

    /* Avoid doing a check twice.  The OK/Reload dialog can cause a focus
     * event and we would keep on checking if the file is steadily growing.
     * Do check again after typing something. */
    if (focus && did_check_timestamps)
    {
	need_check_timestamps = TRUE;
	return FALSE;
    }

    if (!stuff_empty() || global_busy || !typebuf_typed()
			|| autocmd_busy || curbuf_lock > 0 || allbuf_lock > 0)
	need_check_timestamps = TRUE;		/* check later */
    else
    {
	++no_wait_return;
	did_check_timestamps = TRUE;
	already_warned = FALSE;
	FOR_ALL_BUFFERS(buf)
	{
	    /* Only check buffers in a window. */
	    if (buf->b_nwindows > 0)
	    {
		bufref_T bufref;

		set_bufref(&bufref, buf);
		n = buf_check_timestamp(buf, focus);
		if (didit < n)
		    didit = n;
		if (n > 0 && !bufref_valid(&bufref))
		{
		    /* Autocommands have removed the buffer, start at the
		     * first one again. */
		    buf = firstbuf;
		    continue;
		}
	    }
	}
	--no_wait_return;
	need_check_timestamps = FALSE;
	if (need_wait_return && didit == 2)
	{
	    /* make sure msg isn't overwritten */
	    msg_puts("\n");
	    out_flush();
	}
    }
    return didit;
}

/*
 * Move all the lines from buffer "frombuf" to buffer "tobuf".
 * Return OK or FAIL.  When FAIL "tobuf" is incomplete and/or "frombuf" is not
 * empty.
 */
    static int
move_lines(buf_T *frombuf, buf_T *tobuf)
{
    buf_T	*tbuf = curbuf;
    int		retval = OK;
    linenr_T	lnum;
    char_u	*p;

    /* Copy the lines in "frombuf" to "tobuf". */
    curbuf = tobuf;
    for (lnum = 1; lnum <= frombuf->b_ml.ml_line_count; ++lnum)
    {
	p = vim_strsave(ml_get_buf(frombuf, lnum, FALSE));
	if (p == NULL || ml_append(lnum - 1, p, 0, FALSE) == FAIL)
	{
	    vim_free(p);
	    retval = FAIL;
	    break;
	}
	vim_free(p);
    }

    /* Delete all the lines in "frombuf". */
    if (retval != FAIL)
    {
	curbuf = frombuf;
	for (lnum = curbuf->b_ml.ml_line_count; lnum > 0; --lnum)
	    if (ml_delete(lnum, FALSE) == FAIL)
	    {
		/* Oops!  We could try putting back the saved lines, but that
		 * might fail again... */
		retval = FAIL;
		break;
	    }
    }

    curbuf = tbuf;
    return retval;
}

/*
 * Check if buffer "buf" has been changed.
 * Also check if the file for a new buffer unexpectedly appeared.
 * return 1 if a changed buffer was found.
 * return 2 if a message has been displayed.
 * return 0 otherwise.
 */
    int
buf_check_timestamp(
    buf_T	*buf,
    int		focus UNUSED)	/* called for GUI focus event */
{
    stat_T	st;
    int		stat_res;
    int		retval = 0;
    char_u	*path;
    char	*tbuf;
    char	*mesg = NULL;
    char	*mesg2 = "";
    int		helpmesg = FALSE;
    int		reload = FALSE;
    char	*reason;
#if defined(FEAT_CON_DIALOG) || defined(FEAT_GUI_DIALOG)
    int		can_reload = FALSE;
#endif
    off_T	orig_size = buf->b_orig_size;
    int		orig_mode = buf->b_orig_mode;
#ifdef FEAT_GUI
    int		save_mouse_correct = need_mouse_correct;
#endif
    static int	busy = FALSE;
    int		n;
#ifdef FEAT_EVAL
    char_u	*s;
#endif
    bufref_T	bufref;

    set_bufref(&bufref, buf);

    /* If there is no file name, the buffer is not loaded, 'buftype' is
     * set, we are in the middle of a save or being called recursively: ignore
     * this buffer. */
    if (buf->b_ffname == NULL
	    || buf->b_ml.ml_mfp == NULL
	    || !bt_normal(buf)
	    || buf->b_saving
	    || busy
#ifdef FEAT_NETBEANS_INTG
	    || isNetbeansBuffer(buf)
#endif
#ifdef FEAT_TERMINAL
	    || buf->b_term != NULL
#endif
	    )
	return 0;

    if (       !(buf->b_flags & BF_NOTEDITED)
	    && buf->b_mtime != 0
	    && ((stat_res = mch_stat((char *)buf->b_ffname, &st)) < 0
		|| time_differs((long)st.st_mtime, buf->b_mtime)
		|| st.st_size != buf->b_orig_size
#ifdef HAVE_ST_MODE
		|| (int)st.st_mode != buf->b_orig_mode
#else
		|| mch_getperm(buf->b_ffname) != buf->b_orig_mode
#endif
		))
    {
	retval = 1;

	// set b_mtime to stop further warnings (e.g., when executing
	// FileChangedShell autocmd)
	if (stat_res < 0)
	{
	    // When 'autoread' is set we'll check the file again to see if it
	    // re-appears.
	    buf->b_mtime = buf->b_p_ar;
	    buf->b_orig_size = 0;
	    buf->b_orig_mode = 0;
	}
	else
	    buf_store_time(buf, &st, buf->b_ffname);

	/* Don't do anything for a directory.  Might contain the file
	 * explorer. */
	if (mch_isdir(buf->b_fname))
	    ;

	/*
	 * If 'autoread' is set, the buffer has no changes and the file still
	 * exists, reload the buffer.  Use the buffer-local option value if it
	 * was set, the global option value otherwise.
	 */
	else if ((buf->b_p_ar >= 0 ? buf->b_p_ar : p_ar)
				       && !bufIsChanged(buf) && stat_res >= 0)
	    reload = TRUE;
	else
	{
	    if (stat_res < 0)
		reason = "deleted";
	    else if (bufIsChanged(buf))
		reason = "conflict";
	    /*
	     * Check if the file contents really changed to avoid giving a
	     * warning when only the timestamp was set (e.g., checked out of
	     * CVS).  Always warn when the buffer was changed.
	     */
	    else if (orig_size != buf->b_orig_size || buf_contents_changed(buf))
		reason = "changed";
	    else if (orig_mode != buf->b_orig_mode)
		reason = "mode";
	    else
		reason = "time";

	    /*
	     * Only give the warning if there are no FileChangedShell
	     * autocommands.
	     * Avoid being called recursively by setting "busy".
	     */
	    busy = TRUE;
#ifdef FEAT_EVAL
	    set_vim_var_string(VV_FCS_REASON, (char_u *)reason, -1);
	    set_vim_var_string(VV_FCS_CHOICE, (char_u *)"", -1);
#endif
	    ++allbuf_lock;
	    n = apply_autocmds(EVENT_FILECHANGEDSHELL,
				      buf->b_fname, buf->b_fname, FALSE, buf);
	    --allbuf_lock;
	    busy = FALSE;
	    if (n)
	    {
		if (!bufref_valid(&bufref))
		    emsg(_("E246: FileChangedShell autocommand deleted buffer"));
#ifdef FEAT_EVAL
		s = get_vim_var_str(VV_FCS_CHOICE);
		if (STRCMP(s, "reload") == 0 && *reason != 'd')
		    reload = TRUE;
		else if (STRCMP(s, "ask") == 0)
		    n = FALSE;
		else
#endif
		    return 2;
	    }
	    if (!n)
	    {
		if (*reason == 'd')
		    mesg = _("E211: File \"%s\" no longer available");
		else
		{
		    helpmesg = TRUE;
#if defined(FEAT_CON_DIALOG) || defined(FEAT_GUI_DIALOG)
		    can_reload = TRUE;
#endif
		    if (reason[2] == 'n')
		    {
			mesg = _("W12: Warning: File \"%s\" has changed and the buffer was changed in Vim as well");
			mesg2 = _("See \":help W12\" for more info.");
		    }
		    else if (reason[1] == 'h')
		    {
			mesg = _("W11: Warning: File \"%s\" has changed since editing started");
			mesg2 = _("See \":help W11\" for more info.");
		    }
		    else if (*reason == 'm')
		    {
			mesg = _("W16: Warning: Mode of file \"%s\" has changed since editing started");
			mesg2 = _("See \":help W16\" for more info.");
		    }
		    else
			/* Only timestamp changed, store it to avoid a warning
			 * in check_mtime() later. */
			buf->b_mtime_read = buf->b_mtime;
		}
	    }
	}

    }
    else if ((buf->b_flags & BF_NEW) && !(buf->b_flags & BF_NEW_W)
						&& vim_fexists(buf->b_ffname))
    {
	retval = 1;
	mesg = _("W13: Warning: File \"%s\" has been created after editing started");
	buf->b_flags |= BF_NEW_W;
#if defined(FEAT_CON_DIALOG) || defined(FEAT_GUI_DIALOG)
	can_reload = TRUE;
#endif
    }

    if (mesg != NULL)
    {
	path = home_replace_save(buf, buf->b_fname);
	if (path != NULL)
	{
	    if (!helpmesg)
		mesg2 = "";
	    tbuf = (char *)alloc((unsigned)(STRLEN(path) + STRLEN(mesg)
							+ STRLEN(mesg2) + 2));
	    sprintf(tbuf, mesg, path);
#ifdef FEAT_EVAL
	    /* Set warningmsg here, before the unimportant and output-specific
	     * mesg2 has been appended. */
	    set_vim_var_string(VV_WARNINGMSG, (char_u *)tbuf, -1);
#endif
#if defined(FEAT_CON_DIALOG) || defined(FEAT_GUI_DIALOG)
	    if (can_reload)
	    {
		if (*mesg2 != NUL)
		{
		    STRCAT(tbuf, "\n");
		    STRCAT(tbuf, mesg2);
		}
		if (do_dialog(VIM_WARNING, (char_u *)_("Warning"),
			    (char_u *)tbuf,
			  (char_u *)_("&OK\n&Load File"), 1, NULL, TRUE) == 2)
		    reload = TRUE;
	    }
	    else
#endif
	    if (State > NORMAL_BUSY || (State & CMDLINE) || already_warned)
	    {
		if (*mesg2 != NUL)
		{
		    STRCAT(tbuf, "; ");
		    STRCAT(tbuf, mesg2);
		}
		emsg(tbuf);
		retval = 2;
	    }
	    else
	    {
		if (!autocmd_busy)
		{
		    msg_start();
		    msg_puts_attr(tbuf, HL_ATTR(HLF_E) + MSG_HIST);
		    if (*mesg2 != NUL)
			msg_puts_attr(mesg2, HL_ATTR(HLF_W) + MSG_HIST);
		    msg_clr_eos();
		    (void)msg_end();
		    if (emsg_silent == 0)
		    {
			out_flush();
#ifdef FEAT_GUI
			if (!focus)
#endif
			    /* give the user some time to think about it */
			    ui_delay(1000L, TRUE);

			/* don't redraw and erase the message */
			redraw_cmdline = FALSE;
		    }
		}
		already_warned = TRUE;
	    }

	    vim_free(path);
	    vim_free(tbuf);
	}
    }

    if (reload)
    {
	/* Reload the buffer. */
	buf_reload(buf, orig_mode);
#ifdef FEAT_PERSISTENT_UNDO
	if (buf->b_p_udf && buf->b_ffname != NULL)
	{
	    char_u	    hash[UNDO_HASH_SIZE];
	    buf_T	    *save_curbuf = curbuf;

	    /* Any existing undo file is unusable, write it now. */
	    curbuf = buf;
	    u_compute_hash(hash);
	    u_write_undo(NULL, FALSE, buf, hash);
	    curbuf = save_curbuf;
	}
#endif
    }

    /* Trigger FileChangedShell when the file was changed in any way. */
    if (bufref_valid(&bufref) && retval != 0)
	(void)apply_autocmds(EVENT_FILECHANGEDSHELLPOST,
				      buf->b_fname, buf->b_fname, FALSE, buf);
#ifdef FEAT_GUI
    /* restore this in case an autocommand has set it; it would break
     * 'mousefocus' */
    need_mouse_correct = save_mouse_correct;
#endif

    return retval;
}

/*
 * Reload a buffer that is already loaded.
 * Used when the file was changed outside of Vim.
 * "orig_mode" is buf->b_orig_mode before the need for reloading was detected.
 * buf->b_orig_mode may have been reset already.
 */
    void
buf_reload(buf_T *buf, int orig_mode)
{
    exarg_T	ea;
    pos_T	old_cursor;
    linenr_T	old_topline;
    int		old_ro = buf->b_p_ro;
    buf_T	*savebuf;
    bufref_T	bufref;
    int		saved = OK;
    aco_save_T	aco;
    int		flags = READ_NEW;

    /* set curwin/curbuf for "buf" and save some things */
    aucmd_prepbuf(&aco, buf);

    /* We only want to read the text from the file, not reset the syntax
     * highlighting, clear marks, diff status, etc.  Force the fileformat
     * and encoding to be the same. */
    if (prep_exarg(&ea, buf) == OK)
    {
	old_cursor = curwin->w_cursor;
	old_topline = curwin->w_topline;

	if (p_ur < 0 || curbuf->b_ml.ml_line_count <= p_ur)
	{
	    /* Save all the text, so that the reload can be undone.
	     * Sync first so that this is a separate undo-able action. */
	    u_sync(FALSE);
	    saved = u_savecommon(0, curbuf->b_ml.ml_line_count + 1, 0, TRUE);
	    flags |= READ_KEEP_UNDO;
	}

	/*
	 * To behave like when a new file is edited (matters for
	 * BufReadPost autocommands) we first need to delete the current
	 * buffer contents.  But if reading the file fails we should keep
	 * the old contents.  Can't use memory only, the file might be
	 * too big.  Use a hidden buffer to move the buffer contents to.
	 */
	if (BUFEMPTY() || saved == FAIL)
	    savebuf = NULL;
	else
	{
	    /* Allocate a buffer without putting it in the buffer list. */
	    savebuf = buflist_new(NULL, NULL, (linenr_T)1, BLN_DUMMY);
	    set_bufref(&bufref, savebuf);
	    if (savebuf != NULL && buf == curbuf)
	    {
		/* Open the memline. */
		curbuf = savebuf;
		curwin->w_buffer = savebuf;
		saved = ml_open(curbuf);
		curbuf = buf;
		curwin->w_buffer = buf;
	    }
	    if (savebuf == NULL || saved == FAIL || buf != curbuf
				      || move_lines(buf, savebuf) == FAIL)
	    {
		semsg(_("E462: Could not prepare for reloading \"%s\""),
							    buf->b_fname);
		saved = FAIL;
	    }
	}

	if (saved == OK)
	{
	    curbuf->b_flags |= BF_CHECK_RO;	/* check for RO again */
	    keep_filetype = TRUE;		/* don't detect 'filetype' */
	    if (readfile(buf->b_ffname, buf->b_fname, (linenr_T)0,
			(linenr_T)0,
			(linenr_T)MAXLNUM, &ea, flags) != OK)
	    {
#if defined(FEAT_EVAL)
		if (!aborting())
#endif
		    semsg(_("E321: Could not reload \"%s\""), buf->b_fname);
		if (savebuf != NULL && bufref_valid(&bufref) && buf == curbuf)
		{
		    /* Put the text back from the save buffer.  First
		     * delete any lines that readfile() added. */
		    while (!BUFEMPTY())
			if (ml_delete(buf->b_ml.ml_line_count, FALSE) == FAIL)
			    break;
		    (void)move_lines(savebuf, buf);
		}
	    }
	    else if (buf == curbuf)  /* "buf" still valid */
	    {
		/* Mark the buffer as unmodified and free undo info. */
		unchanged(buf, TRUE);
		if ((flags & READ_KEEP_UNDO) == 0)
		{
		    u_blockfree(buf);
		    u_clearall(buf);
		}
		else
		{
		    /* Mark all undo states as changed. */
		    u_unchanged(curbuf);
		}
	    }
	}
	vim_free(ea.cmd);

	if (savebuf != NULL && bufref_valid(&bufref))
	    wipe_buffer(savebuf, FALSE);

#ifdef FEAT_DIFF
	/* Invalidate diff info if necessary. */
	diff_invalidate(curbuf);
#endif

	/* Restore the topline and cursor position and check it (lines may
	 * have been removed). */
	if (old_topline > curbuf->b_ml.ml_line_count)
	    curwin->w_topline = curbuf->b_ml.ml_line_count;
	else
	    curwin->w_topline = old_topline;
	curwin->w_cursor = old_cursor;
	check_cursor();
	update_topline();
	keep_filetype = FALSE;
#ifdef FEAT_FOLDING
	{
	    win_T	*wp;
	    tabpage_T	*tp;

	    /* Update folds unless they are defined manually. */
	    FOR_ALL_TAB_WINDOWS(tp, wp)
		if (wp->w_buffer == curwin->w_buffer
			&& !foldmethodIsManual(wp))
		    foldUpdateAll(wp);
	}
#endif
	/* If the mode didn't change and 'readonly' was set, keep the old
	 * value; the user probably used the ":view" command.  But don't
	 * reset it, might have had a read error. */
	if (orig_mode == curbuf->b_orig_mode)
	    curbuf->b_p_ro |= old_ro;

	/* Modelines must override settings done by autocommands. */
	do_modelines(0);
    }

    /* restore curwin/curbuf and a few other things */
    aucmd_restbuf(&aco);
    /* Careful: autocommands may have made "buf" invalid! */
}

    void
buf_store_time(buf_T *buf, stat_T *st, char_u *fname UNUSED)
{
    buf->b_mtime = (long)st->st_mtime;
    buf->b_orig_size = st->st_size;
#ifdef HAVE_ST_MODE
    buf->b_orig_mode = (int)st->st_mode;
#else
    buf->b_orig_mode = mch_getperm(fname);
#endif
}

/*
 * Adjust the line with missing eol, used for the next write.
 * Used for do_filter(), when the input lines for the filter are deleted.
 */
    void
write_lnum_adjust(linenr_T offset)
{
    if (curbuf->b_no_eol_lnum != 0)	/* only if there is a missing eol */
	curbuf->b_no_eol_lnum += offset;
}

#if defined(TEMPDIRNAMES) || defined(FEAT_EVAL) || defined(PROTO)
/*
 * Delete "name" and everything in it, recursively.
 * return 0 for succes, -1 if some file was not deleted.
 */
    int
delete_recursive(char_u *name)
{
    int result = 0;
    char_u	**files;
    int		file_count;
    int		i;
    char_u	*exp;

    /* A symbolic link to a directory itself is deleted, not the directory it
     * points to. */
    if (
# if defined(UNIX) || defined(MSWIN)
	 mch_isrealdir(name)
# else
	 mch_isdir(name)
# endif
	    )
    {
	vim_snprintf((char *)NameBuff, MAXPATHL, "%s/*", name);
	exp = vim_strsave(NameBuff);
	if (exp == NULL)
	    return -1;
	if (gen_expand_wildcards(1, &exp, &file_count, &files,
	      EW_DIR|EW_FILE|EW_SILENT|EW_ALLLINKS|EW_DODOT|EW_EMPTYOK) == OK)
	{
	    for (i = 0; i < file_count; ++i)
		if (delete_recursive(files[i]) != 0)
		    result = -1;
	    FreeWild(file_count, files);
	}
	else
	    result = -1;
	vim_free(exp);
	(void)mch_rmdir(name);
    }
    else
	result = mch_remove(name) == 0 ? 0 : -1;

    return result;
}
#endif

#if defined(TEMPDIRNAMES) || defined(PROTO)
static long	temp_count = 0;		/* Temp filename counter. */

/*
 * Delete the temp directory and all files it contains.
 */
    void
vim_deltempdir(void)
{
    if (vim_tempdir != NULL)
    {
	/* remove the trailing path separator */
	gettail(vim_tempdir)[-1] = NUL;
	delete_recursive(vim_tempdir);
	VIM_CLEAR(vim_tempdir);
    }
}

/*
 * Directory "tempdir" was created.  Expand this name to a full path and put
 * it in "vim_tempdir".  This avoids that using ":cd" would confuse us.
 * "tempdir" must be no longer than MAXPATHL.
 */
    static void
vim_settempdir(char_u *tempdir)
{
    char_u	*buf;

    buf = alloc((unsigned)MAXPATHL + 2);
    if (buf != NULL)
    {
	if (vim_FullName(tempdir, buf, MAXPATHL, FALSE) == FAIL)
	    STRCPY(buf, tempdir);
	add_pathsep(buf);
	vim_tempdir = vim_strsave(buf);
	vim_free(buf);
    }
}
#endif

/*
 * vim_tempname(): Return a unique name that can be used for a temp file.
 *
 * The temp file is NOT guaranteed to be created.  If "keep" is FALSE it is
 * guaranteed to NOT be created.
 *
 * The returned pointer is to allocated memory.
 * The returned pointer is NULL if no valid name was found.
 */
    char_u  *
vim_tempname(
    int	    extra_char UNUSED,  /* char to use in the name instead of '?' */
    int	    keep UNUSED)
{
#ifdef USE_TMPNAM
    char_u	itmp[L_tmpnam];	/* use tmpnam() */
#elif defined(MSWIN)
    WCHAR	itmp[TEMPNAMELEN];
#else
    char_u	itmp[TEMPNAMELEN];
#endif

#ifdef TEMPDIRNAMES
    static char	*(tempdirs[]) = {TEMPDIRNAMES};
    int		i;
# ifndef EEXIST
    stat_T	st;
# endif

    /*
     * This will create a directory for private use by this instance of Vim.
     * This is done once, and the same directory is used for all temp files.
     * This method avoids security problems because of symlink attacks et al.
     * It's also a bit faster, because we only need to check for an existing
     * file when creating the directory and not for each temp file.
     */
    if (vim_tempdir == NULL)
    {
	/*
	 * Try the entries in TEMPDIRNAMES to create the temp directory.
	 */
	for (i = 0; i < (int)(sizeof(tempdirs) / sizeof(char *)); ++i)
	{
# ifndef HAVE_MKDTEMP
	    size_t	itmplen;
	    long	nr;
	    long	off;
# endif

	    /* Expand $TMP, leave room for "/v1100000/999999999".
	     * Skip the directory check if the expansion fails. */
	    expand_env((char_u *)tempdirs[i], itmp, TEMPNAMELEN - 20);
	    if (itmp[0] != '$' && mch_isdir(itmp))
	    {
		/* directory exists */
		add_pathsep(itmp);

# ifdef HAVE_MKDTEMP
		{
#  if defined(UNIX) || defined(VMS)
		    /* Make sure the umask doesn't remove the executable bit.
		     * "repl" has been reported to use "177". */
		    mode_t	umask_save = umask(077);
#  endif
		    /* Leave room for filename */
		    STRCAT(itmp, "vXXXXXX");
		    if (mkdtemp((char *)itmp) != NULL)
			vim_settempdir(itmp);
#  if defined(UNIX) || defined(VMS)
		    (void)umask(umask_save);
#  endif
		}
# else
		/* Get an arbitrary number of up to 6 digits.  When it's
		 * unlikely that it already exists it will be faster,
		 * otherwise it doesn't matter.  The use of mkdir() avoids any
		 * security problems because of the predictable number. */
		nr = (mch_get_pid() + (long)time(NULL)) % 1000000L;
		itmplen = STRLEN(itmp);

		/* Try up to 10000 different values until we find a name that
		 * doesn't exist. */
		for (off = 0; off < 10000L; ++off)
		{
		    int		r;
#  if defined(UNIX) || defined(VMS)
		    mode_t	umask_save;
#  endif

		    sprintf((char *)itmp + itmplen, "v%ld", nr + off);
#  ifndef EEXIST
		    /* If mkdir() does not set errno to EEXIST, check for
		     * existing file here.  There is a race condition then,
		     * although it's fail-safe. */
		    if (mch_stat((char *)itmp, &st) >= 0)
			continue;
#  endif
#  if defined(UNIX) || defined(VMS)
		    /* Make sure the umask doesn't remove the executable bit.
		     * "repl" has been reported to use "177". */
		    umask_save = umask(077);
#  endif
		    r = vim_mkdir(itmp, 0700);
#  if defined(UNIX) || defined(VMS)
		    (void)umask(umask_save);
#  endif
		    if (r == 0)
		    {
			vim_settempdir(itmp);
			break;
		    }
#  ifdef EEXIST
		    /* If the mkdir() didn't fail because the file/dir exists,
		     * we probably can't create any dir here, try another
		     * place. */
		    if (errno != EEXIST)
#  endif
			break;
		}
# endif /* HAVE_MKDTEMP */
		if (vim_tempdir != NULL)
		    break;
	    }
	}
    }

    if (vim_tempdir != NULL)
    {
	/* There is no need to check if the file exists, because we own the
	 * directory and nobody else creates a file in it. */
	sprintf((char *)itmp, "%s%ld", vim_tempdir, temp_count++);
	return vim_strsave(itmp);
    }

    return NULL;

#else /* TEMPDIRNAMES */

# ifdef MSWIN
    WCHAR	wszTempFile[_MAX_PATH + 1];
    WCHAR	buf4[4];
    char_u	*retval;
    char_u	*p;

    wcscpy(itmp, L"");
    if (GetTempPathW(_MAX_PATH, wszTempFile) == 0)
    {
	wszTempFile[0] = L'.';	// GetTempPathW() failed, use current dir
	wszTempFile[1] = NUL;
    }
    wcscpy(buf4, L"VIM");
    buf4[2] = extra_char;   /* make it "VIa", "VIb", etc. */
    if (GetTempFileNameW(wszTempFile, buf4, 0, itmp) == 0)
	return NULL;
    if (!keep)
	// GetTempFileName() will create the file, we don't want that
	(void)DeleteFileW(itmp);

    // Backslashes in a temp file name cause problems when filtering with
    // "sh".  NOTE: This also checks 'shellcmdflag' to help those people who
    // didn't set 'shellslash'.
    retval = utf16_to_enc(itmp, NULL);
    if (*p_shcf == '-' || p_ssl)
	for (p = retval; *p; ++p)
	    if (*p == '\\')
		*p = '/';
    return retval;

# else // MSWIN

#  ifdef USE_TMPNAM
    char_u	*p;

    /* tmpnam() will make its own name */
    p = tmpnam((char *)itmp);
    if (p == NULL || *p == NUL)
	return NULL;
#  else
    char_u	*p;

#   ifdef VMS_TEMPNAM
    /* mktemp() is not working on VMS.  It seems to be
     * a do-nothing function. Therefore we use tempnam().
     */
    sprintf((char *)itmp, "VIM%c", extra_char);
    p = (char_u *)tempnam("tmp:", (char *)itmp);
    if (p != NULL)
    {
	/* VMS will use '.LIS' if we don't explicitly specify an extension,
	 * and VIM will then be unable to find the file later */
	STRCPY(itmp, p);
	STRCAT(itmp, ".txt");
	free(p);
    }
    else
	return NULL;
#   else
    STRCPY(itmp, TEMPNAME);
    if ((p = vim_strchr(itmp, '?')) != NULL)
	*p = extra_char;
    if (mktemp((char *)itmp) == NULL)
	return NULL;
#   endif
#  endif

    return vim_strsave(itmp);
# endif // MSWIN
#endif /* TEMPDIRNAMES */
}

#if defined(BACKSLASH_IN_FILENAME) || defined(PROTO)
/*
 * Convert all backslashes in fname to forward slashes in-place, unless when
 * it looks like a URL.
 */
    void
forward_slash(char_u *fname)
{
    char_u	*p;

    if (path_with_url(fname))
	return;
    for (p = fname; *p != NUL; ++p)
	/* The Big5 encoding can have '\' in the trail byte. */
	if (enc_dbcs != 0 && (*mb_ptr2len)(p) > 1)
	    ++p;
	else if (*p == '\\')
	    *p = '/';
}
#endif

/*
 * Try matching a filename with a "pattern" ("prog" is NULL), or use the
 * precompiled regprog "prog" ("pattern" is NULL).  That avoids calling
 * vim_regcomp() often.
 * Used for autocommands and 'wildignore'.
 * Returns TRUE if there is a match, FALSE otherwise.
 */
    int
match_file_pat(
    char_u	*pattern,		/* pattern to match with */
    regprog_T	**prog,			/* pre-compiled regprog or NULL */
    char_u	*fname,			/* full path of file name */
    char_u	*sfname,		/* short file name or NULL */
    char_u	*tail,			/* tail of path */
    int		allow_dirs)		/* allow matching with dir */
{
    regmatch_T	regmatch;
    int		result = FALSE;

    regmatch.rm_ic = p_fic; /* ignore case if 'fileignorecase' is set */
    if (prog != NULL)
	regmatch.regprog = *prog;
    else
	regmatch.regprog = vim_regcomp(pattern, RE_MAGIC);

    /*
     * Try for a match with the pattern with:
     * 1. the full file name, when the pattern has a '/'.
     * 2. the short file name, when the pattern has a '/'.
     * 3. the tail of the file name, when the pattern has no '/'.
     */
    if (regmatch.regprog != NULL
	     && ((allow_dirs
		     && (vim_regexec(&regmatch, fname, (colnr_T)0)
			 || (sfname != NULL
			     && vim_regexec(&regmatch, sfname, (colnr_T)0))))
		 || (!allow_dirs && vim_regexec(&regmatch, tail, (colnr_T)0))))
	result = TRUE;

    if (prog != NULL)
	*prog = regmatch.regprog;
    else
	vim_regfree(regmatch.regprog);
    return result;
}

#if defined(FEAT_WILDIGN) || defined(PROTO)
/*
 * Return TRUE if a file matches with a pattern in "list".
 * "list" is a comma-separated list of patterns, like 'wildignore'.
 * "sfname" is the short file name or NULL, "ffname" the long file name.
 */
    int
match_file_list(char_u *list, char_u *sfname, char_u *ffname)
{
    char_u	buf[100];
    char_u	*tail;
    char_u	*regpat;
    char	allow_dirs;
    int		match;
    char_u	*p;

    tail = gettail(sfname);

    /* try all patterns in 'wildignore' */
    p = list;
    while (*p)
    {
	copy_option_part(&p, buf, 100, ",");
	regpat = file_pat_to_reg_pat(buf, NULL, &allow_dirs, FALSE);
	if (regpat == NULL)
	    break;
	match = match_file_pat(regpat, NULL, ffname, sfname,
						       tail, (int)allow_dirs);
	vim_free(regpat);
	if (match)
	    return TRUE;
    }
    return FALSE;
}
#endif

/*
 * Convert the given pattern "pat" which has shell style wildcards in it, into
 * a regular expression, and return the result in allocated memory.  If there
 * is a directory path separator to be matched, then TRUE is put in
 * allow_dirs, otherwise FALSE is put there -- webb.
 * Handle backslashes before special characters, like "\*" and "\ ".
 *
 * Returns NULL when out of memory.
 */
    char_u *
file_pat_to_reg_pat(
    char_u	*pat,
    char_u	*pat_end,	/* first char after pattern or NULL */
    char	*allow_dirs,	/* Result passed back out in here */
    int		no_bslash UNUSED) /* Don't use a backward slash as pathsep */
{
    int		size = 2; /* '^' at start, '$' at end */
    char_u	*endp;
    char_u	*reg_pat;
    char_u	*p;
    int		i;
    int		nested = 0;
    int		add_dollar = TRUE;

    if (allow_dirs != NULL)
	*allow_dirs = FALSE;
    if (pat_end == NULL)
	pat_end = pat + STRLEN(pat);

    for (p = pat; p < pat_end; p++)
    {
	switch (*p)
	{
	    case '*':
	    case '.':
	    case ',':
	    case '{':
	    case '}':
	    case '~':
		size += 2;	/* extra backslash */
		break;
#ifdef BACKSLASH_IN_FILENAME
	    case '\\':
	    case '/':
		size += 4;	/* could become "[\/]" */
		break;
#endif
	    default:
		size++;
		if (enc_dbcs != 0 && (*mb_ptr2len)(p) > 1)
		{
		    ++p;
		    ++size;
		}
		break;
	}
    }
    reg_pat = alloc(size + 1);
    if (reg_pat == NULL)
	return NULL;

    i = 0;

    if (pat[0] == '*')
	while (pat[0] == '*' && pat < pat_end - 1)
	    pat++;
    else
	reg_pat[i++] = '^';
    endp = pat_end - 1;
    if (endp >= pat && *endp == '*')
    {
	while (endp - pat > 0 && *endp == '*')
	    endp--;
	add_dollar = FALSE;
    }
    for (p = pat; *p && nested >= 0 && p <= endp; p++)
    {
	switch (*p)
	{
	    case '*':
		reg_pat[i++] = '.';
		reg_pat[i++] = '*';
		while (p[1] == '*')	/* "**" matches like "*" */
		    ++p;
		break;
	    case '.':
	    case '~':
		reg_pat[i++] = '\\';
		reg_pat[i++] = *p;
		break;
	    case '?':
		reg_pat[i++] = '.';
		break;
	    case '\\':
		if (p[1] == NUL)
		    break;
#ifdef BACKSLASH_IN_FILENAME
		if (!no_bslash)
		{
		    /* translate:
		     * "\x" to "\\x"  e.g., "dir\file"
		     * "\*" to "\\.*" e.g., "dir\*.c"
		     * "\?" to "\\."  e.g., "dir\??.c"
		     * "\+" to "\+"   e.g., "fileX\+.c"
		     */
		    if ((vim_isfilec(p[1]) || p[1] == '*' || p[1] == '?')
			    && p[1] != '+')
		    {
			reg_pat[i++] = '[';
			reg_pat[i++] = '\\';
			reg_pat[i++] = '/';
			reg_pat[i++] = ']';
			if (allow_dirs != NULL)
			    *allow_dirs = TRUE;
			break;
		    }
		}
#endif
		/* Undo escaping from ExpandEscape():
		 * foo\?bar -> foo?bar
		 * foo\%bar -> foo%bar
		 * foo\,bar -> foo,bar
		 * foo\ bar -> foo bar
		 * Don't unescape \, * and others that are also special in a
		 * regexp.
		 * An escaped { must be unescaped since we use magic not
		 * verymagic.  Use "\\\{n,m\}"" to get "\{n,m}".
		 */
		if (*++p == '?'
#ifdef BACKSLASH_IN_FILENAME
			&& no_bslash
#endif
			)
		    reg_pat[i++] = '?';
		else
		    if (*p == ',' || *p == '%' || *p == '#'
			       || vim_isspace(*p) || *p == '{' || *p == '}')
			reg_pat[i++] = *p;
		    else if (*p == '\\' && p[1] == '\\' && p[2] == '{')
		    {
			reg_pat[i++] = '\\';
			reg_pat[i++] = '{';
			p += 2;
		    }
		    else
		    {
			if (allow_dirs != NULL && vim_ispathsep(*p)
#ifdef BACKSLASH_IN_FILENAME
				&& (!no_bslash || *p != '\\')
#endif
				)
			    *allow_dirs = TRUE;
			reg_pat[i++] = '\\';
			reg_pat[i++] = *p;
		    }
		break;
#ifdef BACKSLASH_IN_FILENAME
	    case '/':
		reg_pat[i++] = '[';
		reg_pat[i++] = '\\';
		reg_pat[i++] = '/';
		reg_pat[i++] = ']';
		if (allow_dirs != NULL)
		    *allow_dirs = TRUE;
		break;
#endif
	    case '{':
		reg_pat[i++] = '\\';
		reg_pat[i++] = '(';
		nested++;
		break;
	    case '}':
		reg_pat[i++] = '\\';
		reg_pat[i++] = ')';
		--nested;
		break;
	    case ',':
		if (nested)
		{
		    reg_pat[i++] = '\\';
		    reg_pat[i++] = '|';
		}
		else
		    reg_pat[i++] = ',';
		break;
	    default:
		if (enc_dbcs != 0 && (*mb_ptr2len)(p) > 1)
		    reg_pat[i++] = *p++;
		else if (allow_dirs != NULL && vim_ispathsep(*p))
		    *allow_dirs = TRUE;
		reg_pat[i++] = *p;
		break;
	}
    }
    if (add_dollar)
	reg_pat[i++] = '$';
    reg_pat[i] = NUL;
    if (nested != 0)
    {
	if (nested < 0)
	    emsg(_("E219: Missing {."));
	else
	    emsg(_("E220: Missing }."));
	VIM_CLEAR(reg_pat);
    }
    return reg_pat;
}

#if defined(EINTR) || defined(PROTO)
/*
 * Version of read() that retries when interrupted by EINTR (possibly
 * by a SIGWINCH).
 */
    long
read_eintr(int fd, void *buf, size_t bufsize)
{
    long ret;

    for (;;)
    {
	ret = vim_read(fd, buf, bufsize);
	if (ret >= 0 || errno != EINTR)
	    break;
    }
    return ret;
}

/*
 * Version of write() that retries when interrupted by EINTR (possibly
 * by a SIGWINCH).
 */
    long
write_eintr(int fd, void *buf, size_t bufsize)
{
    long    ret = 0;
    long    wlen;

    /* Repeat the write() so long it didn't fail, other than being interrupted
     * by a signal. */
    while (ret < (long)bufsize)
    {
	wlen = vim_write(fd, (char *)buf + ret, bufsize - ret);
	if (wlen < 0)
	{
	    if (errno != EINTR)
		break;
	}
	else
	    ret += wlen;
    }
    return ret;
}
#endif