Add mksh from CVS 2010/08/24 as system/core/mksh module

Both shells (ash from system/core/sh, and mksh) are built by
default but only the one where $(TARGET_SHELL) is set to is
actually installed (the shell and the mkshrc configuration
file are tagged shell_mksh for this to work).

Signed-off-by: Thorsten Glaser <tg@mirbsd.org>
diff --git a/mksh/src/jobs.c b/mksh/src/jobs.c
new file mode 100644
index 0000000..47326a1
--- /dev/null
+++ b/mksh/src/jobs.c
@@ -0,0 +1,1648 @@
+/*	$OpenBSD: jobs.c,v 1.38 2009/12/12 04:28:44 deraadt Exp $	*/
+
+/*-
+ * Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009
+ *	Thorsten Glaser <tg@mirbsd.org>
+ *
+ * Provided that these terms and disclaimer and all copyright notices
+ * are retained or reproduced in an accompanying document, permission
+ * is granted to deal in this work without restriction, including un-
+ * limited rights to use, publicly perform, distribute, sell, modify,
+ * merge, give away, or sublicence.
+ *
+ * This work is provided "AS IS" and WITHOUT WARRANTY of any kind, to
+ * the utmost extent permitted by applicable law, neither express nor
+ * implied; without malicious intent or gross negligence. In no event
+ * may a licensor, author or contributor be held liable for indirect,
+ * direct, other damage, loss, or other issues arising in any way out
+ * of dealing in the work, even if advised of the possibility of such
+ * damage or existence of a defect, except proven that it results out
+ * of said person's immediate fault when using the work as intended.
+ */
+
+#include "sh.h"
+
+__RCSID("$MirOS: src/bin/mksh/jobs.c,v 1.69 2010/07/04 17:33:54 tg Exp $");
+
+#if HAVE_KILLPG
+#define mksh_killpg		killpg
+#else
+/* cross fingers and hope kill is killpg-endowed */
+#define mksh_killpg(p,s)	kill(-(p), (s))
+#endif
+
+/* Order important! */
+#define PRUNNING	0
+#define PEXITED		1
+#define PSIGNALLED	2
+#define PSTOPPED	3
+
+typedef struct proc	Proc;
+struct proc {
+	Proc *next;		/* next process in pipeline (if any) */
+	pid_t pid;		/* process id */
+	int state;
+	int status;		/* wait status */
+	char command[48];	/* process command string */
+};
+
+/* Notify/print flag - j_print() argument */
+#define JP_NONE		0	/* don't print anything */
+#define JP_SHORT	1	/* print signals processes were killed by */
+#define JP_MEDIUM	2	/* print [job-num] -/+ command */
+#define JP_LONG		3	/* print [job-num] -/+ pid command */
+#define JP_PGRP		4	/* print pgrp */
+
+/* put_job() flags */
+#define PJ_ON_FRONT	0	/* at very front */
+#define PJ_PAST_STOPPED	1	/* just past any stopped jobs */
+
+/* Job.flags values */
+#define JF_STARTED	0x001	/* set when all processes in job are started */
+#define JF_WAITING	0x002	/* set if j_waitj() is waiting on job */
+#define JF_W_ASYNCNOTIFY 0x004	/* set if waiting and async notification ok */
+#define JF_XXCOM	0x008	/* set for $(command) jobs */
+#define JF_FG		0x010	/* running in foreground (also has tty pgrp) */
+#define JF_SAVEDTTY	0x020	/* j->ttystate is valid */
+#define JF_CHANGED	0x040	/* process has changed state */
+#define JF_KNOWN	0x080	/* $! referenced */
+#define JF_ZOMBIE	0x100	/* known, unwaited process */
+#define JF_REMOVE	0x200	/* flagged for removal (j_jobs()/j_noityf()) */
+#define JF_USETTYMODE	0x400	/* tty mode saved if process exits normally */
+#define JF_SAVEDTTYPGRP	0x800	/* j->saved_ttypgrp is valid */
+
+typedef struct job Job;
+struct job {
+	Job *next;		/* next job in list */
+	Proc *proc_list;	/* process list */
+	Proc *last_proc;	/* last process in list */
+	struct timeval systime;	/* system time used by job */
+	struct timeval usrtime;	/* user time used by job */
+	pid_t pgrp;		/* process group of job */
+	pid_t ppid;		/* pid of process that forked job */
+	int job;		/* job number: %n */
+	int flags;		/* see JF_* */
+	volatile int state;	/* job state */
+	int status;		/* exit status of last process */
+	int32_t	age;		/* number of jobs started */
+	Coproc_id coproc_id;	/* 0 or id of coprocess output pipe */
+#ifndef MKSH_UNEMPLOYED
+	struct termios ttystate;/* saved tty state for stopped jobs */
+	pid_t saved_ttypgrp;	/* saved tty process group for stopped jobs */
+#endif
+};
+
+/* Flags for j_waitj() */
+#define JW_NONE		0x00
+#define JW_INTERRUPT	0x01	/* ^C will stop the wait */
+#define JW_ASYNCNOTIFY	0x02	/* asynchronous notification during wait ok */
+#define JW_STOPPEDWAIT	0x04	/* wait even if job stopped */
+
+/* Error codes for j_lookup() */
+#define JL_OK		0
+#define JL_NOSUCH	1	/* no such job */
+#define JL_AMBIG	2	/* %foo or %?foo is ambiguous */
+#define JL_INVALID	3	/* non-pid, non-% job id */
+
+static const char *const lookup_msgs[] = {
+	null,
+	"no such job",
+	"ambiguous",
+	"argument must be %job or process id",
+	NULL
+};
+
+static Job *job_list;		/* job list */
+static Job *last_job;
+static Job *async_job;
+static pid_t async_pid;
+
+static int nzombie;		/* # of zombies owned by this process */
+static int32_t njobs;		/* # of jobs started */
+
+#ifndef CHILD_MAX
+#define CHILD_MAX	25
+#endif
+
+/* held_sigchld is set if sigchld occurs before a job is completely started */
+static volatile sig_atomic_t held_sigchld;
+
+#ifndef MKSH_UNEMPLOYED
+static struct shf	*shl_j;
+static bool		ttypgrp_ok;	/* set if can use tty pgrps */
+static pid_t		restore_ttypgrp = -1;
+static int const	tt_sigs[] = { SIGTSTP, SIGTTIN, SIGTTOU };
+#endif
+
+static void		j_set_async(Job *);
+static void		j_startjob(Job *);
+static int		j_waitj(Job *, int, const char *);
+static void		j_sigchld(int);
+static void		j_print(Job *, int, struct shf *);
+static Job		*j_lookup(const char *, int *);
+static Job		*new_job(void);
+static Proc		*new_proc(void);
+static void		check_job(Job *);
+static void		put_job(Job *, int);
+static void		remove_job(Job *, const char *);
+static int		kill_job(Job *, int);
+
+/* initialise job control */
+void
+j_init(void)
+{
+#ifndef MKSH_UNEMPLOYED
+	bool mflagset = Flag(FMONITOR) != 127;
+
+	Flag(FMONITOR) = 0;
+#endif
+
+	(void)sigemptyset(&sm_default);
+	sigprocmask(SIG_SETMASK, &sm_default, NULL);
+
+	(void)sigemptyset(&sm_sigchld);
+	(void)sigaddset(&sm_sigchld, SIGCHLD);
+
+	setsig(&sigtraps[SIGCHLD], j_sigchld,
+	    SS_RESTORE_ORIG|SS_FORCE|SS_SHTRAP);
+
+#ifndef MKSH_UNEMPLOYED
+	if (!mflagset && Flag(FTALKING))
+		Flag(FMONITOR) = 1;
+
+	/*
+	 * shl_j is used to do asynchronous notification (used in
+	 * an interrupt handler, so need a distinct shf)
+	 */
+	shl_j = shf_fdopen(2, SHF_WR, NULL);
+
+	if (Flag(FMONITOR) || Flag(FTALKING)) {
+		int i;
+
+		/*
+		 * the TF_SHELL_USES test is a kludge that lets us know if
+		 * if the signals have been changed by the shell.
+		 */
+		for (i = NELEM(tt_sigs); --i >= 0; ) {
+			sigtraps[tt_sigs[i]].flags |= TF_SHELL_USES;
+			/* j_change() sets this to SS_RESTORE_DFL if FMONITOR */
+			setsig(&sigtraps[tt_sigs[i]], SIG_IGN,
+			    SS_RESTORE_IGN|SS_FORCE);
+		}
+	}
+
+	/* j_change() calls tty_init() */
+	if (Flag(FMONITOR))
+		j_change();
+	else
+#endif
+	  if (Flag(FTALKING))
+		tty_init(true, true);
+}
+
+/* job cleanup before shell exit */
+void
+j_exit(void)
+{
+	/* kill stopped, and possibly running, jobs */
+	Job	*j;
+	int	killed = 0;
+
+	for (j = job_list; j != NULL; j = j->next) {
+		if (j->ppid == procpid &&
+		    (j->state == PSTOPPED ||
+		    (j->state == PRUNNING &&
+		    ((j->flags & JF_FG) ||
+		    (Flag(FLOGIN) && !Flag(FNOHUP) && procpid == kshpid))))) {
+			killed = 1;
+			if (j->pgrp == 0)
+				kill_job(j, SIGHUP);
+			else
+				mksh_killpg(j->pgrp, SIGHUP);
+#ifndef MKSH_UNEMPLOYED
+			if (j->state == PSTOPPED) {
+				if (j->pgrp == 0)
+					kill_job(j, SIGCONT);
+				else
+					mksh_killpg(j->pgrp, SIGCONT);
+			}
+#endif
+		}
+	}
+	if (killed)
+		sleep(1);
+	j_notify();
+
+#ifndef MKSH_UNEMPLOYED
+	if (kshpid == procpid && restore_ttypgrp >= 0) {
+		/*
+		 * Need to restore the tty pgrp to what it was when the
+		 * shell started up, so that the process that started us
+		 * will be able to access the tty when we are done.
+		 * Also need to restore our process group in case we are
+		 * about to do an exec so that both our parent and the
+		 * process we are to become will be able to access the tty.
+		 */
+		tcsetpgrp(tty_fd, restore_ttypgrp);
+		setpgid(0, restore_ttypgrp);
+	}
+	if (Flag(FMONITOR)) {
+		Flag(FMONITOR) = 0;
+		j_change();
+	}
+#endif
+}
+
+#ifndef MKSH_UNEMPLOYED
+/* turn job control on or off according to Flag(FMONITOR) */
+void
+j_change(void)
+{
+	int i;
+
+	if (Flag(FMONITOR)) {
+		bool use_tty = Flag(FTALKING);
+
+		/* Don't call tcgetattr() 'til we own the tty process group */
+		if (use_tty)
+			tty_init(false, true);
+
+		/* no controlling tty, no SIGT* */
+		if ((ttypgrp_ok = use_tty && tty_fd >= 0 && tty_devtty)) {
+			setsig(&sigtraps[SIGTTIN], SIG_DFL,
+			    SS_RESTORE_ORIG|SS_FORCE);
+			/* wait to be given tty (POSIX.1, B.2, job control) */
+			while (1) {
+				pid_t ttypgrp;
+
+				if ((ttypgrp = tcgetpgrp(tty_fd)) < 0) {
+					warningf(false,
+					    "j_init: tcgetpgrp() failed: %s",
+					    strerror(errno));
+					ttypgrp_ok = false;
+					break;
+				}
+				if (ttypgrp == kshpgrp)
+					break;
+				kill(0, SIGTTIN);
+			}
+		}
+		for (i = NELEM(tt_sigs); --i >= 0; )
+			setsig(&sigtraps[tt_sigs[i]], SIG_IGN,
+			    SS_RESTORE_DFL|SS_FORCE);
+		if (ttypgrp_ok && kshpgrp != kshpid) {
+			if (setpgid(0, kshpid) < 0) {
+				warningf(false,
+				    "j_init: setpgid() failed: %s",
+				    strerror(errno));
+				ttypgrp_ok = false;
+			} else {
+				if (tcsetpgrp(tty_fd, kshpid) < 0) {
+					warningf(false,
+					    "j_init: tcsetpgrp() failed: %s",
+					    strerror(errno));
+					ttypgrp_ok = false;
+				} else
+					restore_ttypgrp = kshpgrp;
+				kshpgrp = kshpid;
+			}
+		}
+		if (use_tty && !ttypgrp_ok)
+			warningf(false, "warning: won't have full job control");
+		if (tty_fd >= 0)
+			tcgetattr(tty_fd, &tty_state);
+	} else {
+		ttypgrp_ok = false;
+		if (Flag(FTALKING))
+			for (i = NELEM(tt_sigs); --i >= 0; )
+				setsig(&sigtraps[tt_sigs[i]], SIG_IGN,
+				    SS_RESTORE_IGN|SS_FORCE);
+		else
+			for (i = NELEM(tt_sigs); --i >= 0; ) {
+				if (sigtraps[tt_sigs[i]].flags &
+				    (TF_ORIG_IGN | TF_ORIG_DFL))
+					setsig(&sigtraps[tt_sigs[i]],
+					    (sigtraps[tt_sigs[i]].flags & TF_ORIG_IGN) ?
+					    SIG_IGN : SIG_DFL,
+					    SS_RESTORE_ORIG|SS_FORCE);
+			}
+		if (!Flag(FTALKING))
+			tty_close();
+	}
+}
+#endif
+
+/* execute tree in child subprocess */
+int
+exchild(struct op *t, int flags,
+    volatile int *xerrok,
+    /* used if XPCLOSE or XCCLOSE */ int close_fd)
+{
+	static Proc *last_proc;		/* for pipelines */
+
+	int rv = 0, forksleep;
+	sigset_t omask;
+	struct {
+		Proc *p;
+		Job *j;
+		pid_t cldpid;
+	} pi;
+
+	if (flags & XEXEC)
+		/*
+		 * Clear XFORK|XPCLOSE|XCCLOSE|XCOPROC|XPIPEO|XPIPEI|XXCOM|XBGND
+		 * (also done in another execute() below)
+		 */
+		return (execute(t, flags & (XEXEC | XERROK), xerrok));
+
+	/* no SIGCHLDs while messing with job and process lists */
+	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
+
+	pi.p = new_proc();
+	pi.p->next = NULL;
+	pi.p->state = PRUNNING;
+	pi.p->status = 0;
+	pi.p->pid = 0;
+
+	/* link process into jobs list */
+	if (flags & XPIPEI) {
+		/* continuing with a pipe */
+		if (!last_job)
+			internal_errorf(
+			    "exchild: XPIPEI and no last_job - pid %d",
+			    (int)procpid);
+		pi.j = last_job;
+		if (last_proc)
+			last_proc->next = pi.p;
+		last_proc = pi.p;
+	} else {
+		pi.j = new_job(); /* fills in pi.j->job */
+		/*
+		 * we don't consider XXCOMs foreground since they don't get
+		 * tty process group and we don't save or restore tty modes.
+		 */
+		pi.j->flags = (flags & XXCOM) ? JF_XXCOM :
+		    ((flags & XBGND) ? 0 : (JF_FG|JF_USETTYMODE));
+		timerclear(&pi.j->usrtime);
+		timerclear(&pi.j->systime);
+		pi.j->state = PRUNNING;
+		pi.j->pgrp = 0;
+		pi.j->ppid = procpid;
+		pi.j->age = ++njobs;
+		pi.j->proc_list = pi.p;
+		pi.j->coproc_id = 0;
+		last_job = pi.j;
+		last_proc = pi.p;
+		put_job(pi.j, PJ_PAST_STOPPED);
+	}
+
+	snptreef(pi.p->command, sizeof(pi.p->command), "%T", t);
+
+	/* create child process */
+	forksleep = 1;
+	while ((pi.cldpid = fork()) < 0 && errno == EAGAIN && forksleep < 32) {
+		if (intrsig)	 /* allow user to ^C out... */
+			break;
+		sleep(forksleep);
+		forksleep <<= 1;
+	}
+	if (pi.cldpid < 0) {
+		kill_job(pi.j, SIGKILL);
+		remove_job(pi.j, "fork failed");
+		sigprocmask(SIG_SETMASK, &omask, NULL);
+		errorf("cannot fork - try again");
+	}
+	pi.p->pid = pi.cldpid ? pi.cldpid : (procpid = getpid());
+
+	/*
+	 * ensure next child gets a (slightly) different $RANDOM sequence
+	 * from its parent process and other child processes
+	 */
+	change_random(&pi, sizeof(pi));
+
+#ifndef MKSH_UNEMPLOYED
+	/* job control set up */
+	if (Flag(FMONITOR) && !(flags&XXCOM)) {
+		int	dotty = 0;
+		if (pi.j->pgrp == 0) {	/* First process */
+			pi.j->pgrp = pi.p->pid;
+			dotty = 1;
+		}
+
+		/* set pgrp in both parent and child to deal with race
+		 * condition
+		 */
+		setpgid(pi.p->pid, pi.j->pgrp);
+		if (ttypgrp_ok && dotty && !(flags & XBGND))
+			tcsetpgrp(tty_fd, pi.j->pgrp);
+	}
+#endif
+
+	/* used to close pipe input fd */
+	if (close_fd >= 0 && (((flags & XPCLOSE) && pi.cldpid) ||
+	    ((flags & XCCLOSE) && !pi.cldpid)))
+		close(close_fd);
+	if (!pi.cldpid) {
+		/* child */
+
+		/* Do this before restoring signal */
+		if (flags & XCOPROC)
+			coproc_cleanup(false);
+		sigprocmask(SIG_SETMASK, &omask, NULL);
+		cleanup_parents_env();
+#ifndef MKSH_UNEMPLOYED
+		/* If FMONITOR or FTALKING is set, these signals are ignored,
+		 * if neither FMONITOR nor FTALKING are set, the signals have
+		 * their inherited values.
+		 */
+		if (Flag(FMONITOR) && !(flags & XXCOM)) {
+			for (forksleep = NELEM(tt_sigs); --forksleep >= 0; )
+				setsig(&sigtraps[tt_sigs[forksleep]], SIG_DFL,
+				    SS_RESTORE_DFL|SS_FORCE);
+		}
+#endif
+#if HAVE_NICE
+		if (Flag(FBGNICE) && (flags & XBGND))
+			(void)nice(4);
+#endif
+		if ((flags & XBGND)
+#ifndef MKSH_UNEMPLOYED
+		    && !Flag(FMONITOR)
+#endif
+		    ) {
+			setsig(&sigtraps[SIGINT], SIG_IGN,
+			    SS_RESTORE_IGN|SS_FORCE);
+			setsig(&sigtraps[SIGQUIT], SIG_IGN,
+			    SS_RESTORE_IGN|SS_FORCE);
+			if ((!(flags & (XPIPEI | XCOPROC))) &&
+			    ((forksleep = open("/dev/null", 0)) > 0)) {
+				(void)ksh_dup2(forksleep, 0, true);
+				close(forksleep);
+			}
+		}
+		remove_job(pi.j, "child");	/* in case of $(jobs) command */
+		nzombie = 0;
+#ifndef MKSH_UNEMPLOYED
+		ttypgrp_ok = false;
+		Flag(FMONITOR) = 0;
+#endif
+		Flag(FTALKING) = 0;
+		tty_close();
+		cleartraps();
+		/* no return */
+		execute(t, (flags & XERROK) | XEXEC, NULL);
+#ifndef MKSH_SMALL
+		if (t->type == TPIPE)
+			unwind(LLEAVE);
+		internal_warningf("exchild: execute() returned");
+		fptreef(shl_out, 2, "exchild: tried to execute {\n%T\n}\n", t);
+		shf_flush(shl_out);
+#endif
+		unwind(LLEAVE);
+		/* NOTREACHED */
+	}
+
+	/* shell (parent) stuff */
+	if (!(flags & XPIPEO)) {	/* last process in a job */
+		j_startjob(pi.j);
+		if (flags & XCOPROC) {
+			pi.j->coproc_id = coproc.id;
+			/* n jobs using co-process output */
+			coproc.njobs++;
+			/* j using co-process input */
+			coproc.job = (void *)pi.j;
+		}
+		if (flags & XBGND) {
+			j_set_async(pi.j);
+			if (Flag(FTALKING)) {
+				shf_fprintf(shl_out, "[%d]", pi.j->job);
+				for (pi.p = pi.j->proc_list; pi.p;
+				    pi.p = pi.p->next)
+					shf_fprintf(shl_out, " %d",
+					    (int)pi.p->pid);
+				shf_putchar('\n', shl_out);
+				shf_flush(shl_out);
+			}
+		} else
+			rv = j_waitj(pi.j, JW_NONE, "jw:last proc");
+	}
+
+	sigprocmask(SIG_SETMASK, &omask, NULL);
+
+	return (rv);
+}
+
+/* start the last job: only used for $(command) jobs */
+void
+startlast(void)
+{
+	sigset_t omask;
+
+	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
+
+	if (last_job) { /* no need to report error - waitlast() will do it */
+		/* ensure it isn't removed by check_job() */
+		last_job->flags |= JF_WAITING;
+		j_startjob(last_job);
+	}
+	sigprocmask(SIG_SETMASK, &omask, NULL);
+}
+
+/* wait for last job: only used for $(command) jobs */
+int
+waitlast(void)
+{
+	int	rv;
+	Job	*j;
+	sigset_t omask;
+
+	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
+
+	j = last_job;
+	if (!j || !(j->flags & JF_STARTED)) {
+		if (!j)
+			warningf(true, "waitlast: no last job");
+		else
+			internal_warningf("waitlast: not started");
+		sigprocmask(SIG_SETMASK, &omask, NULL);
+		return (125); /* not so arbitrary, non-zero value */
+	}
+
+	rv = j_waitj(j, JW_NONE, "jw:waitlast");
+
+	sigprocmask(SIG_SETMASK, &omask, NULL);
+
+	return (rv);
+}
+
+/* wait for child, interruptable. */
+int
+waitfor(const char *cp, int *sigp)
+{
+	int	rv;
+	Job	*j;
+	int	ecode;
+	int	flags = JW_INTERRUPT|JW_ASYNCNOTIFY;
+	sigset_t omask;
+
+	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
+
+	*sigp = 0;
+
+	if (cp == NULL) {
+		/*
+		 * wait for an unspecified job - always returns 0, so
+		 * don't have to worry about exited/signaled jobs
+		 */
+		for (j = job_list; j; j = j->next)
+			/* AT&T ksh will wait for stopped jobs - we don't */
+			if (j->ppid == procpid && j->state == PRUNNING)
+				break;
+		if (!j) {
+			sigprocmask(SIG_SETMASK, &omask, NULL);
+			return (-1);
+		}
+	} else if ((j = j_lookup(cp, &ecode))) {
+		/* don't report normal job completion */
+		flags &= ~JW_ASYNCNOTIFY;
+		if (j->ppid != procpid) {
+			sigprocmask(SIG_SETMASK, &omask, NULL);
+			return (-1);
+		}
+	} else {
+		sigprocmask(SIG_SETMASK, &omask, NULL);
+		if (ecode != JL_NOSUCH)
+			bi_errorf("%s: %s", cp, lookup_msgs[ecode]);
+		return (-1);
+	}
+
+	/* AT&T ksh will wait for stopped jobs - we don't */
+	rv = j_waitj(j, flags, "jw:waitfor");
+
+	sigprocmask(SIG_SETMASK, &omask, NULL);
+
+	if (rv < 0) /* we were interrupted */
+		*sigp = 128 + -rv;
+
+	return (rv);
+}
+
+/* kill (built-in) a job */
+int
+j_kill(const char *cp, int sig)
+{
+	Job	*j;
+	int	rv = 0;
+	int	ecode;
+	sigset_t omask;
+
+	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
+
+	if ((j = j_lookup(cp, &ecode)) == NULL) {
+		sigprocmask(SIG_SETMASK, &omask, NULL);
+		bi_errorf("%s: %s", cp, lookup_msgs[ecode]);
+		return (1);
+	}
+
+	if (j->pgrp == 0) {	/* started when !Flag(FMONITOR) */
+		if (kill_job(j, sig) < 0) {
+			bi_errorf("%s: %s", cp, strerror(errno));
+			rv = 1;
+		}
+	} else {
+#ifndef MKSH_UNEMPLOYED
+		if (j->state == PSTOPPED && (sig == SIGTERM || sig == SIGHUP))
+			mksh_killpg(j->pgrp, SIGCONT);
+#endif
+		if (mksh_killpg(j->pgrp, sig) < 0) {
+			bi_errorf("%s: %s", cp, strerror(errno));
+			rv = 1;
+		}
+	}
+
+	sigprocmask(SIG_SETMASK, &omask, NULL);
+
+	return (rv);
+}
+
+#ifndef MKSH_UNEMPLOYED
+/* fg and bg built-ins: called only if Flag(FMONITOR) set */
+int
+j_resume(const char *cp, int bg)
+{
+	Job	*j;
+	Proc	*p;
+	int	ecode;
+	int	running;
+	int	rv = 0;
+	sigset_t omask;
+
+	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
+
+	if ((j = j_lookup(cp, &ecode)) == NULL) {
+		sigprocmask(SIG_SETMASK, &omask, NULL);
+		bi_errorf("%s: %s", cp, lookup_msgs[ecode]);
+		return (1);
+	}
+
+	if (j->pgrp == 0) {
+		sigprocmask(SIG_SETMASK, &omask, NULL);
+		bi_errorf("job not job-controlled");
+		return (1);
+	}
+
+	if (bg)
+		shprintf("[%d] ", j->job);
+
+	running = 0;
+	for (p = j->proc_list; p != NULL; p = p->next) {
+		if (p->state == PSTOPPED) {
+			p->state = PRUNNING;
+			p->status = 0;
+			running = 1;
+		}
+		shf_puts(p->command, shl_stdout);
+		if (p->next)
+			shf_puts("| ", shl_stdout);
+	}
+	shf_putc('\n', shl_stdout);
+	shf_flush(shl_stdout);
+	if (running)
+		j->state = PRUNNING;
+
+	put_job(j, PJ_PAST_STOPPED);
+	if (bg)
+		j_set_async(j);
+	else {
+		/* attach tty to job */
+		if (j->state == PRUNNING) {
+			if (ttypgrp_ok && (j->flags & JF_SAVEDTTY))
+				tcsetattr(tty_fd, TCSADRAIN, &j->ttystate);
+			/* See comment in j_waitj regarding saved_ttypgrp. */
+			if (ttypgrp_ok &&
+			    tcsetpgrp(tty_fd, (j->flags & JF_SAVEDTTYPGRP) ?
+			    j->saved_ttypgrp : j->pgrp) < 0) {
+				rv = errno;
+				if (j->flags & JF_SAVEDTTY)
+					tcsetattr(tty_fd, TCSADRAIN, &tty_state);
+				sigprocmask(SIG_SETMASK, &omask,
+				    NULL);
+				bi_errorf("1st tcsetpgrp(%d, %d) failed: %s",
+				    tty_fd,
+				    (int)((j->flags & JF_SAVEDTTYPGRP) ?
+				    j->saved_ttypgrp : j->pgrp),
+				    strerror(rv));
+				return (1);
+			}
+		}
+		j->flags |= JF_FG;
+		j->flags &= ~JF_KNOWN;
+		if (j == async_job)
+			async_job = NULL;
+	}
+
+	if (j->state == PRUNNING && mksh_killpg(j->pgrp, SIGCONT) < 0) {
+		int err = errno;
+
+		if (!bg) {
+			j->flags &= ~JF_FG;
+			if (ttypgrp_ok && (j->flags & JF_SAVEDTTY))
+				tcsetattr(tty_fd, TCSADRAIN, &tty_state);
+			if (ttypgrp_ok && tcsetpgrp(tty_fd, kshpgrp) < 0)
+				warningf(true,
+				    "fg: 2nd tcsetpgrp(%d, %ld) failed: %s",
+				    tty_fd, (long)kshpgrp, strerror(errno));
+		}
+		sigprocmask(SIG_SETMASK, &omask, NULL);
+		bi_errorf("cannot continue job %s: %s",
+		    cp, strerror(err));
+		return (1);
+	}
+	if (!bg) {
+		if (ttypgrp_ok) {
+			j->flags &= ~(JF_SAVEDTTY | JF_SAVEDTTYPGRP);
+		}
+		rv = j_waitj(j, JW_NONE, "jw:resume");
+	}
+	sigprocmask(SIG_SETMASK, &omask, NULL);
+	return (rv);
+}
+#endif
+
+/* are there any running or stopped jobs ? */
+int
+j_stopped_running(void)
+{
+	Job	*j;
+	int	which = 0;
+
+	for (j = job_list; j != NULL; j = j->next) {
+#ifndef MKSH_UNEMPLOYED
+		if (j->ppid == procpid && j->state == PSTOPPED)
+			which |= 1;
+#endif
+		if (Flag(FLOGIN) && !Flag(FNOHUP) && procpid == kshpid &&
+		    j->ppid == procpid && j->state == PRUNNING)
+			which |= 2;
+	}
+	if (which) {
+		shellf("You have %s%s%s jobs\n",
+		    which & 1 ? "stopped" : "",
+		    which == 3 ? " and " : "",
+		    which & 2 ? "running" : "");
+		return (1);
+	}
+
+	return (0);
+}
+
+int
+j_njobs(void)
+{
+	Job *j;
+	int nj = 0;
+	sigset_t omask;
+
+	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
+	for (j = job_list; j; j = j->next)
+		nj++;
+
+	sigprocmask(SIG_SETMASK, &omask, NULL);
+	return (nj);
+}
+
+
+/* list jobs for jobs built-in */
+int
+j_jobs(const char *cp, int slp,
+    int nflag)		/* 0: short, 1: long, 2: pgrp */
+{
+	Job	*j, *tmp;
+	int	how;
+	int	zflag = 0;
+	sigset_t omask;
+
+	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
+
+	if (nflag < 0) { /* kludge: print zombies */
+		nflag = 0;
+		zflag = 1;
+	}
+	if (cp) {
+		int	ecode;
+
+		if ((j = j_lookup(cp, &ecode)) == NULL) {
+			sigprocmask(SIG_SETMASK, &omask, NULL);
+			bi_errorf("%s: %s", cp, lookup_msgs[ecode]);
+			return (1);
+		}
+	} else
+		j = job_list;
+	how = slp == 0 ? JP_MEDIUM : (slp == 1 ? JP_LONG : JP_PGRP);
+	for (; j; j = j->next) {
+		if ((!(j->flags & JF_ZOMBIE) || zflag) &&
+		    (!nflag || (j->flags & JF_CHANGED))) {
+			j_print(j, how, shl_stdout);
+			if (j->state == PEXITED || j->state == PSIGNALLED)
+				j->flags |= JF_REMOVE;
+		}
+		if (cp)
+			break;
+	}
+	/* Remove jobs after printing so there won't be multiple + or - jobs */
+	for (j = job_list; j; j = tmp) {
+		tmp = j->next;
+		if (j->flags & JF_REMOVE)
+			remove_job(j, "jobs");
+	}
+	sigprocmask(SIG_SETMASK, &omask, NULL);
+	return (0);
+}
+
+/* list jobs for top-level notification */
+void
+j_notify(void)
+{
+	Job	*j, *tmp;
+	sigset_t omask;
+
+	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
+	for (j = job_list; j; j = j->next) {
+#ifndef MKSH_UNEMPLOYED
+		if (Flag(FMONITOR) && (j->flags & JF_CHANGED))
+			j_print(j, JP_MEDIUM, shl_out);
+#endif
+		/* Remove job after doing reports so there aren't
+		 * multiple +/- jobs.
+		 */
+		if (j->state == PEXITED || j->state == PSIGNALLED)
+			j->flags |= JF_REMOVE;
+	}
+	for (j = job_list; j; j = tmp) {
+		tmp = j->next;
+		if (j->flags & JF_REMOVE)
+			remove_job(j, "notify");
+	}
+	shf_flush(shl_out);
+	sigprocmask(SIG_SETMASK, &omask, NULL);
+}
+
+/* Return pid of last process in last asynchronous job */
+pid_t
+j_async(void)
+{
+	sigset_t omask;
+
+	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
+
+	if (async_job)
+		async_job->flags |= JF_KNOWN;
+
+	sigprocmask(SIG_SETMASK, &omask, NULL);
+
+	return (async_pid);
+}
+
+/*
+ * Make j the last async process
+ *
+ * If jobs are compiled in then this routine expects sigchld to be blocked.
+ */
+static void
+j_set_async(Job *j)
+{
+	Job	*jl, *oldest;
+
+	if (async_job && (async_job->flags & (JF_KNOWN|JF_ZOMBIE)) == JF_ZOMBIE)
+		remove_job(async_job, "async");
+	if (!(j->flags & JF_STARTED)) {
+		internal_warningf("j_async: job not started");
+		return;
+	}
+	async_job = j;
+	async_pid = j->last_proc->pid;
+	while (nzombie > CHILD_MAX) {
+		oldest = NULL;
+		for (jl = job_list; jl; jl = jl->next)
+			if (jl != async_job && (jl->flags & JF_ZOMBIE) &&
+			    (!oldest || jl->age < oldest->age))
+				oldest = jl;
+		if (!oldest) {
+			/* XXX debugging */
+			if (!(async_job->flags & JF_ZOMBIE) || nzombie != 1) {
+				internal_warningf("j_async: bad nzombie (%d)",
+				    nzombie);
+				nzombie = 0;
+			}
+			break;
+		}
+		remove_job(oldest, "zombie");
+	}
+}
+
+/*
+ * Start a job: set STARTED, check for held signals and set j->last_proc
+ *
+ * If jobs are compiled in then this routine expects sigchld to be blocked.
+ */
+static void
+j_startjob(Job *j)
+{
+	Proc	*p;
+
+	j->flags |= JF_STARTED;
+	for (p = j->proc_list; p->next; p = p->next)
+		;
+	j->last_proc = p;
+
+	if (held_sigchld) {
+		held_sigchld = 0;
+		/* Don't call j_sigchld() as it may remove job... */
+		kill(procpid, SIGCHLD);
+	}
+}
+
+/*
+ * wait for job to complete or change state
+ *
+ * If jobs are compiled in then this routine expects sigchld to be blocked.
+ */
+static int
+j_waitj(Job *j,
+    int flags,			/* see JW_* */
+    const char *where)
+{
+	int	rv;
+
+	/*
+	 * No auto-notify on the job we are waiting on.
+	 */
+	j->flags |= JF_WAITING;
+	if (flags & JW_ASYNCNOTIFY)
+		j->flags |= JF_W_ASYNCNOTIFY;
+
+#ifndef MKSH_UNEMPLOYED
+	if (!Flag(FMONITOR))
+#endif
+		flags |= JW_STOPPEDWAIT;
+
+	while (j->state == PRUNNING ||
+	    ((flags & JW_STOPPEDWAIT) && j->state == PSTOPPED)) {
+		sigsuspend(&sm_default);
+		if (fatal_trap) {
+			int oldf = j->flags & (JF_WAITING|JF_W_ASYNCNOTIFY);
+			j->flags &= ~(JF_WAITING|JF_W_ASYNCNOTIFY);
+			runtraps(TF_FATAL);
+			j->flags |= oldf; /* not reached... */
+		}
+		if ((flags & JW_INTERRUPT) && (rv = trap_pending())) {
+			j->flags &= ~(JF_WAITING|JF_W_ASYNCNOTIFY);
+			return (-rv);
+		}
+	}
+	j->flags &= ~(JF_WAITING|JF_W_ASYNCNOTIFY);
+
+	if (j->flags & JF_FG) {
+		j->flags &= ~JF_FG;
+#ifndef MKSH_UNEMPLOYED
+		if (Flag(FMONITOR) && ttypgrp_ok && j->pgrp) {
+			/*
+			 * Save the tty's current pgrp so it can be restored
+			 * when the job is foregrounded. This is to
+			 * deal with things like the GNU su which does
+			 * a fork/exec instead of an exec (the fork means
+			 * the execed shell gets a different pid from its
+			 * pgrp, so naturally it sets its pgrp and gets hosed
+			 * when it gets foregrounded by the parent shell which
+			 * has restored the tty's pgrp to that of the su
+			 * process).
+			 */
+			if (j->state == PSTOPPED &&
+			    (j->saved_ttypgrp = tcgetpgrp(tty_fd)) >= 0)
+				j->flags |= JF_SAVEDTTYPGRP;
+			if (tcsetpgrp(tty_fd, kshpgrp) < 0)
+				warningf(true,
+				    "j_waitj: tcsetpgrp(%d, %ld) failed: %s",
+				    tty_fd, (long)kshpgrp, strerror(errno));
+			if (j->state == PSTOPPED) {
+				j->flags |= JF_SAVEDTTY;
+				tcgetattr(tty_fd, &j->ttystate);
+			}
+		}
+#endif
+		if (tty_fd >= 0) {
+			/*
+			 * Only restore tty settings if job was originally
+			 * started in the foreground. Problems can be
+			 * caused by things like 'more foobar &' which will
+			 * typically get and save the shell's vi/emacs tty
+			 * settings before setting up the tty for itself;
+			 * when more exits, it restores the 'original'
+			 * settings, and things go down hill from there...
+			 */
+			if (j->state == PEXITED && j->status == 0 &&
+			    (j->flags & JF_USETTYMODE)) {
+				tcgetattr(tty_fd, &tty_state);
+			} else {
+				tcsetattr(tty_fd, TCSADRAIN, &tty_state);
+				/*-
+				 * Don't use tty mode if job is stopped and
+				 * later restarted and exits. Consider
+				 * the sequence:
+				 *	vi foo (stopped)
+				 *	...
+				 *	stty something
+				 *	...
+				 *	fg (vi; ZZ)
+				 * mode should be that of the stty, not what
+				 * was before the vi started.
+				 */
+				if (j->state == PSTOPPED)
+					j->flags &= ~JF_USETTYMODE;
+			}
+		}
+#ifndef MKSH_UNEMPLOYED
+		/*
+		 * If it looks like user hit ^C to kill a job, pretend we got
+		 * one too to break out of for loops, etc. (AT&T ksh does this
+		 * even when not monitoring, but this doesn't make sense since
+		 * a tty generated ^C goes to the whole process group)
+		 */
+		{
+			int status;
+
+			status = j->last_proc->status;
+			if (Flag(FMONITOR) && j->state == PSIGNALLED &&
+			    WIFSIGNALED(status) &&
+			    (sigtraps[WTERMSIG(status)].flags & TF_TTY_INTR))
+				trapsig(WTERMSIG(status));
+		}
+#endif
+	}
+
+	j_usrtime = j->usrtime;
+	j_systime = j->systime;
+	rv = j->status;
+
+	if (!(flags & JW_ASYNCNOTIFY)
+#ifndef MKSH_UNEMPLOYED
+	    && (!Flag(FMONITOR) || j->state != PSTOPPED)
+#endif
+	    ) {
+		j_print(j, JP_SHORT, shl_out);
+		shf_flush(shl_out);
+	}
+	if (j->state != PSTOPPED
+#ifndef MKSH_UNEMPLOYED
+	    && (!Flag(FMONITOR) || !(flags & JW_ASYNCNOTIFY))
+#endif
+	    )
+		remove_job(j, where);
+
+	return (rv);
+}
+
+/*
+ * SIGCHLD handler to reap children and update job states
+ *
+ * If jobs are compiled in then this routine expects sigchld to be blocked.
+ */
+/* ARGSUSED */
+static void
+j_sigchld(int sig MKSH_A_UNUSED)
+{
+	/* this runs inside interrupt context, with errno saved */
+
+	Job *j;
+	Proc *p = NULL;
+	pid_t pid;
+	int status;
+	struct rusage ru0, ru1;
+
+	/*
+	 * Don't wait for any processes if a job is partially started.
+	 * This is so we don't do away with the process group leader
+	 * before all the processes in a pipe line are started (so the
+	 * setpgid() won't fail)
+	 */
+	for (j = job_list; j; j = j->next)
+		if (j->ppid == procpid && !(j->flags & JF_STARTED)) {
+			held_sigchld = 1;
+			return;
+		}
+
+	getrusage(RUSAGE_CHILDREN, &ru0);
+	do {
+		pid = waitpid(-1, &status, (WNOHANG|WUNTRACED));
+
+		/*
+		 * return if this would block (0) or no children
+		 * or interrupted (-1)
+		 */
+		if (pid <= 0)
+			return;
+
+		getrusage(RUSAGE_CHILDREN, &ru1);
+
+		/* find job and process structures for this pid */
+		for (j = job_list; j != NULL; j = j->next)
+			for (p = j->proc_list; p != NULL; p = p->next)
+				if (p->pid == pid)
+					goto found;
+ found:
+		if (j == NULL) {
+			/* Can occur if process has kids, then execs shell
+			warningf(true, "bad process waited for (pid = %d)",
+				pid);
+			 */
+			ru0 = ru1;
+			continue;
+		}
+
+		timeradd(&j->usrtime, &ru1.ru_utime, &j->usrtime);
+		timersub(&j->usrtime, &ru0.ru_utime, &j->usrtime);
+		timeradd(&j->systime, &ru1.ru_stime, &j->systime);
+		timersub(&j->systime, &ru0.ru_stime, &j->systime);
+		ru0 = ru1;
+		p->status = status;
+#ifndef MKSH_UNEMPLOYED
+		if (WIFSTOPPED(status))
+			p->state = PSTOPPED;
+		else
+#endif
+		  if (WIFSIGNALED(status))
+			p->state = PSIGNALLED;
+		else
+			p->state = PEXITED;
+
+		check_job(j);	/* check to see if entire job is done */
+	} while (1);
+}
+
+/*
+ * Called only when a process in j has exited/stopped (ie, called only
+ * from j_sigchld()). If no processes are running, the job status
+ * and state are updated, asynchronous job notification is done and,
+ * if unneeded, the job is removed.
+ *
+ * If jobs are compiled in then this routine expects sigchld to be blocked.
+ */
+static void
+check_job(Job *j)
+{
+	int	jstate;
+	Proc	*p;
+
+	/* XXX debugging (nasty - interrupt routine using shl_out) */
+	if (!(j->flags & JF_STARTED)) {
+		internal_warningf("check_job: job started (flags 0x%x)",
+		    j->flags);
+		return;
+	}
+
+	jstate = PRUNNING;
+	for (p=j->proc_list; p != NULL; p = p->next) {
+		if (p->state == PRUNNING)
+			return;	/* some processes still running */
+		if (p->state > jstate)
+			jstate = p->state;
+	}
+	j->state = jstate;
+
+	switch (j->last_proc->state) {
+	case PEXITED:
+		j->status = WEXITSTATUS(j->last_proc->status);
+		break;
+	case PSIGNALLED:
+		j->status = 128 + WTERMSIG(j->last_proc->status);
+		break;
+	default:
+		j->status = 0;
+		break;
+	}
+
+	/*
+	 * Note when co-process dies: can't be done in j_wait() nor
+	 * remove_job() since neither may be called for non-interactive
+	 * shells.
+	 */
+	if (j->state == PEXITED || j->state == PSIGNALLED) {
+		/*
+		 * No need to keep co-process input any more
+		 * (at least, this is what ksh93d thinks)
+		 */
+		if (coproc.job == j) {
+			coproc.job = NULL;
+			/*
+			 * XXX would be nice to get the closes out of here
+			 * so they aren't done in the signal handler.
+			 * Would mean a check in coproc_getfd() to
+			 * do "if job == 0 && write >= 0, close write".
+			 */
+			coproc_write_close(coproc.write);
+		}
+		/* Do we need to keep the output? */
+		if (j->coproc_id && j->coproc_id == coproc.id &&
+		    --coproc.njobs == 0)
+			coproc_readw_close(coproc.read);
+	}
+
+	j->flags |= JF_CHANGED;
+#ifndef MKSH_UNEMPLOYED
+	if (Flag(FMONITOR) && !(j->flags & JF_XXCOM)) {
+		/*
+		 * Only put stopped jobs at the front to avoid confusing
+		 * the user (don't want finished jobs effecting %+ or %-)
+		 */
+		if (j->state == PSTOPPED)
+			put_job(j, PJ_ON_FRONT);
+		if (Flag(FNOTIFY) &&
+		    (j->flags & (JF_WAITING|JF_W_ASYNCNOTIFY)) != JF_WAITING) {
+			/* Look for the real file descriptor 2 */
+			{
+				struct env *ep;
+				int fd = 2;
+
+				for (ep = e; ep; ep = ep->oenv)
+					if (ep->savefd && ep->savefd[2])
+						fd = ep->savefd[2];
+				shf_reopen(fd, SHF_WR, shl_j);
+			}
+			/*
+			 * Can't call j_notify() as it removes jobs. The job
+			 * must stay in the job list as j_waitj() may be
+			 * running with this job.
+			 */
+			j_print(j, JP_MEDIUM, shl_j);
+			shf_flush(shl_j);
+			if (!(j->flags & JF_WAITING) && j->state != PSTOPPED)
+				remove_job(j, "notify");
+		}
+	}
+#endif
+	if (
+#ifndef MKSH_UNEMPLOYED
+	    !Flag(FMONITOR) &&
+#endif
+	    !(j->flags & (JF_WAITING|JF_FG)) &&
+	    j->state != PSTOPPED) {
+		if (j == async_job || (j->flags & JF_KNOWN)) {
+			j->flags |= JF_ZOMBIE;
+			j->job = -1;
+			nzombie++;
+		} else
+			remove_job(j, "checkjob");
+	}
+}
+
+/*
+ * Print job status in either short, medium or long format.
+ *
+ * If jobs are compiled in then this routine expects sigchld to be blocked.
+ */
+static void
+j_print(Job *j, int how, struct shf *shf)
+{
+	Proc	*p;
+	int	state;
+	int	status;
+	int	coredumped;
+	char	jobchar = ' ';
+	char	buf[64];
+	const char *filler;
+	int	output = 0;
+
+	if (how == JP_PGRP) {
+		/*
+		 * POSIX doesn't say what to do it there is no process
+		 * group leader (ie, !FMONITOR). We arbitrarily return
+		 * last pid (which is what $! returns).
+		 */
+		shf_fprintf(shf, "%d\n", (int)(j->pgrp ? j->pgrp :
+		    (j->last_proc ? j->last_proc->pid : 0)));
+		return;
+	}
+	j->flags &= ~JF_CHANGED;
+	filler = j->job > 10 ? "\n       " : "\n      ";
+	if (j == job_list)
+		jobchar = '+';
+	else if (j == job_list->next)
+		jobchar = '-';
+
+	for (p = j->proc_list; p != NULL;) {
+		coredumped = 0;
+		switch (p->state) {
+		case PRUNNING:
+			memcpy(buf, "Running", 8);
+			break;
+		case PSTOPPED:
+			strlcpy(buf, sigtraps[WSTOPSIG(p->status)].mess,
+			    sizeof(buf));
+			break;
+		case PEXITED:
+			if (how == JP_SHORT)
+				buf[0] = '\0';
+			else if (WEXITSTATUS(p->status) == 0)
+				memcpy(buf, "Done", 5);
+			else
+				shf_snprintf(buf, sizeof(buf), "Done (%d)",
+				    WEXITSTATUS(p->status));
+			break;
+		case PSIGNALLED:
+#ifdef WCOREDUMP
+			if (WCOREDUMP(p->status))
+				coredumped = 1;
+#endif
+			/*
+			 * kludge for not reporting 'normal termination
+			 * signals' (i.e. SIGINT, SIGPIPE)
+			 */
+			if (how == JP_SHORT && !coredumped &&
+			    (WTERMSIG(p->status) == SIGINT ||
+			    WTERMSIG(p->status) == SIGPIPE)) {
+				buf[0] = '\0';
+			} else
+				strlcpy(buf, sigtraps[WTERMSIG(p->status)].mess,
+				    sizeof(buf));
+			break;
+		}
+
+		if (how != JP_SHORT) {
+			if (p == j->proc_list)
+				shf_fprintf(shf, "[%d] %c ", j->job, jobchar);
+			else
+				shf_fprintf(shf, "%s", filler);
+		}
+
+		if (how == JP_LONG)
+			shf_fprintf(shf, "%5d ", (int)p->pid);
+
+		if (how == JP_SHORT) {
+			if (buf[0]) {
+				output = 1;
+				shf_fprintf(shf, "%s%s ",
+				    buf, coredumped ? " (core dumped)" : null);
+			}
+		} else {
+			output = 1;
+			shf_fprintf(shf, "%-20s %s%s%s", buf, p->command,
+			    p->next ? "|" : null,
+			    coredumped ? " (core dumped)" : null);
+		}
+
+		state = p->state;
+		status = p->status;
+		p = p->next;
+		while (p && p->state == state && p->status == status) {
+			if (how == JP_LONG)
+				shf_fprintf(shf, "%s%5d %-20s %s%s", filler,
+				    (int)p->pid, " ", p->command,
+				    p->next ? "|" : null);
+			else if (how == JP_MEDIUM)
+				shf_fprintf(shf, " %s%s", p->command,
+				    p->next ? "|" : null);
+			p = p->next;
+		}
+	}
+	if (output)
+		shf_putc('\n', shf);
+}
+
+/*
+ * Convert % sequence to job
+ *
+ * If jobs are compiled in then this routine expects sigchld to be blocked.
+ */
+static Job *
+j_lookup(const char *cp, int *ecodep)
+{
+	Job		*j, *last_match;
+	Proc		*p;
+	int		len, job = 0;
+
+	if (ksh_isdigit(*cp)) {
+		getn(cp, &job);
+		/* Look for last_proc->pid (what $! returns) first... */
+		for (j = job_list; j != NULL; j = j->next)
+			if (j->last_proc && j->last_proc->pid == job)
+				return (j);
+		/*
+		 * ...then look for process group (this is non-POSIX,
+		 * but should not break anything
+		 */
+		for (j = job_list; j != NULL; j = j->next)
+			if (j->pgrp && j->pgrp == job)
+				return (j);
+		if (ecodep)
+			*ecodep = JL_NOSUCH;
+		return (NULL);
+	}
+	if (*cp != '%') {
+		if (ecodep)
+			*ecodep = JL_INVALID;
+		return (NULL);
+	}
+	switch (*++cp) {
+	case '\0': /* non-standard */
+	case '+':
+	case '%':
+		if (job_list != NULL)
+			return (job_list);
+		break;
+
+	case '-':
+		if (job_list != NULL && job_list->next)
+			return (job_list->next);
+		break;
+
+	case '0': case '1': case '2': case '3': case '4':
+	case '5': case '6': case '7': case '8': case '9':
+		getn(cp, &job);
+		for (j = job_list; j != NULL; j = j->next)
+			if (j->job == job)
+				return (j);
+		break;
+
+	case '?':		/* %?string */
+		last_match = NULL;
+		for (j = job_list; j != NULL; j = j->next)
+			for (p = j->proc_list; p != NULL; p = p->next)
+				if (strstr(p->command, cp+1) != NULL) {
+					if (last_match) {
+						if (ecodep)
+							*ecodep = JL_AMBIG;
+						return (NULL);
+					}
+					last_match = j;
+				}
+		if (last_match)
+			return (last_match);
+		break;
+
+	default:		/* %string */
+		len = strlen(cp);
+		last_match = NULL;
+		for (j = job_list; j != NULL; j = j->next)
+			if (strncmp(cp, j->proc_list->command, len) == 0) {
+				if (last_match) {
+					if (ecodep)
+						*ecodep = JL_AMBIG;
+					return (NULL);
+				}
+				last_match = j;
+			}
+		if (last_match)
+			return (last_match);
+		break;
+	}
+	if (ecodep)
+		*ecodep = JL_NOSUCH;
+	return (NULL);
+}
+
+static Job	*free_jobs;
+static Proc	*free_procs;
+
+/*
+ * allocate a new job and fill in the job number.
+ *
+ * If jobs are compiled in then this routine expects sigchld to be blocked.
+ */
+static Job *
+new_job(void)
+{
+	int	i;
+	Job	*newj, *j;
+
+	if (free_jobs != NULL) {
+		newj = free_jobs;
+		free_jobs = free_jobs->next;
+	} else
+		newj = alloc(sizeof(Job), APERM);
+
+	/* brute force method */
+	for (i = 1; ; i++) {
+		for (j = job_list; j && j->job != i; j = j->next)
+			;
+		if (j == NULL)
+			break;
+	}
+	newj->job = i;
+
+	return (newj);
+}
+
+/*
+ * Allocate new process struct
+ *
+ * If jobs are compiled in then this routine expects sigchld to be blocked.
+ */
+static Proc *
+new_proc(void)
+{
+	Proc	*p;
+
+	if (free_procs != NULL) {
+		p = free_procs;
+		free_procs = free_procs->next;
+	} else
+		p = alloc(sizeof(Proc), APERM);
+
+	return (p);
+}
+
+/*
+ * Take job out of job_list and put old structures into free list.
+ * Keeps nzombies, last_job and async_job up to date.
+ *
+ * If jobs are compiled in then this routine expects sigchld to be blocked.
+ */
+static void
+remove_job(Job *j, const char *where)
+{
+	Proc	*p, *tmp;
+	Job	**prev, *curr;
+
+	prev = &job_list;
+	curr = *prev;
+	for (; curr != NULL && curr != j; prev = &curr->next, curr = *prev)
+		;
+	if (curr != j) {
+		internal_warningf("remove_job: job not found (%s)", where);
+		return;
+	}
+	*prev = curr->next;
+
+	/* free up proc structures */
+	for (p = j->proc_list; p != NULL; ) {
+		tmp = p;
+		p = p->next;
+		tmp->next = free_procs;
+		free_procs = tmp;
+	}
+
+	if ((j->flags & JF_ZOMBIE) && j->ppid == procpid)
+		--nzombie;
+	j->next = free_jobs;
+	free_jobs = j;
+
+	if (j == last_job)
+		last_job = NULL;
+	if (j == async_job)
+		async_job = NULL;
+}
+
+/*
+ * put j in a particular location (taking it out job_list if it is there
+ * already)
+ *
+ * If jobs are compiled in then this routine expects sigchld to be blocked.
+ */
+static void
+put_job(Job *j, int where)
+{
+	Job	**prev, *curr;
+
+	/* Remove job from list (if there) */
+	prev = &job_list;
+	curr = job_list;
+	for (; curr && curr != j; prev = &curr->next, curr = *prev)
+		;
+	if (curr == j)
+		*prev = curr->next;
+
+	switch (where) {
+	case PJ_ON_FRONT:
+		j->next = job_list;
+		job_list = j;
+		break;
+
+	case PJ_PAST_STOPPED:
+		prev = &job_list;
+		curr = job_list;
+		for (; curr && curr->state == PSTOPPED; prev = &curr->next,
+		    curr = *prev)
+			;
+		j->next = curr;
+		*prev = j;
+		break;
+	}
+}
+
+/*
+ * nuke a job (called when unable to start full job).
+ *
+ * If jobs are compiled in then this routine expects sigchld to be blocked.
+ */
+static int
+kill_job(Job *j, int sig)
+{
+	Proc	*p;
+	int	rval = 0;
+
+	for (p = j->proc_list; p != NULL; p = p->next)
+		if (p->pid != 0)
+			if (kill(p->pid, sig) < 0)
+				rval = -1;
+	return (rval);
+}