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<H1 class="no-header">curs_terminfo 3x 2024-04-13 ncurses 6.5 Library calls</H1>
<PRE>
<STRONG><A HREF="curs_terminfo.3x.html">curs_terminfo(3x)</A></STRONG> Library calls <STRONG><A HREF="curs_terminfo.3x.html">curs_terminfo(3x)</A></STRONG>
</PRE><H2><a name="h2-NAME">NAME</a></H2><PRE>
<STRONG>del_curterm</STRONG>, <STRONG>mvcur</STRONG>, <STRONG>putp</STRONG>, <STRONG>restartterm</STRONG>, <STRONG>set_curterm</STRONG>, <STRONG>setupterm</STRONG>,
<STRONG>tigetflag</STRONG>, <STRONG>tigetnum</STRONG>, <STRONG>tigetstr</STRONG>, <STRONG>tiparm</STRONG>, <STRONG>tiparm_s</STRONG>, <STRONG>tiscan_s</STRONG>, <STRONG>tparm</STRONG>,
<STRONG>tputs</STRONG>, <STRONG>vid_attr</STRONG>, <STRONG>vid_puts</STRONG>, <STRONG>vidattr</STRONG>, <STRONG>vidputs</STRONG> - <EM>curses</EM> interfaces to
<EM>terminfo</EM> database
</PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
<STRONG>#include</STRONG> <STRONG>&lt;curses.h&gt;</STRONG>
<STRONG>#include</STRONG> <STRONG>&lt;term.h&gt;</STRONG>
<STRONG>TERMINAL</STRONG> <STRONG>*cur_term;</STRONG>
<STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG> <STRONG>const</STRONG> <STRONG>boolnames[];</STRONG>
<STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG> <STRONG>const</STRONG> <STRONG>boolcodes[];</STRONG>
<STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG> <STRONG>const</STRONG> <STRONG>boolfnames[];</STRONG>
<STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG> <STRONG>const</STRONG> <STRONG>numnames[];</STRONG>
<STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG> <STRONG>const</STRONG> <STRONG>numcodes[];</STRONG>
<STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG> <STRONG>const</STRONG> <STRONG>numfnames[];</STRONG>
<STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG> <STRONG>const</STRONG> <STRONG>strnames[];</STRONG>
<STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG> <STRONG>const</STRONG> <STRONG>strcodes[];</STRONG>
<STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG> <STRONG>const</STRONG> <STRONG>strfnames[];</STRONG>
<STRONG>int</STRONG> <STRONG>setupterm(const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>term</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>filedes</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <STRONG>*</STRONG><EM>errret</EM><STRONG>);</STRONG>
<STRONG>TERMINAL</STRONG> <STRONG>*set_curterm(TERMINAL</STRONG> <STRONG>*</STRONG><EM>nterm</EM><STRONG>);</STRONG>
<STRONG>int</STRONG> <STRONG>del_curterm(TERMINAL</STRONG> <STRONG>*</STRONG><EM>oterm</EM><STRONG>);</STRONG>
<STRONG>int</STRONG> <STRONG>restartterm(const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>term</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>filedes</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <STRONG>*</STRONG><EM>errret</EM><STRONG>);</STRONG>
<STRONG>char</STRONG> <STRONG>*tparm(const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>str</EM><STRONG>,</STRONG> ...<STRONG>);</STRONG>
<EM>/*</EM> <EM>or</EM> <EM>*/</EM>
<STRONG>char</STRONG> <STRONG>*tparm(const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>str</EM><STRONG>,</STRONG> <STRONG>long</STRONG> <EM>p1</EM> ... <STRONG>long</STRONG> <EM>p9</EM><STRONG>);</STRONG>
<STRONG>int</STRONG> <STRONG>tputs(const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>str</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>affcnt</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <STRONG>(*</STRONG><EM>putc</EM><STRONG>)(int));</STRONG>
<STRONG>int</STRONG> <STRONG>putp(const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>str</EM><STRONG>);</STRONG>
<STRONG>int</STRONG> <STRONG>vidputs(chtype</STRONG> <EM>attrs</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <STRONG>(*</STRONG><EM>putc</EM><STRONG>)(int));</STRONG>
<STRONG>int</STRONG> <STRONG>vidattr(chtype</STRONG> <EM>attrs</EM><STRONG>);</STRONG>
<STRONG>int</STRONG> <STRONG>vid_puts(attr_t</STRONG> <EM>attrs</EM><STRONG>,</STRONG> <STRONG>short</STRONG> <EM>pair</EM><STRONG>,</STRONG> <STRONG>void</STRONG> <STRONG>*</STRONG><EM>opts</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <STRONG>(*</STRONG><EM>putc</EM><STRONG>)(int));</STRONG>
<STRONG>int</STRONG> <STRONG>vid_attr(attr_t</STRONG> <EM>attrs</EM><STRONG>,</STRONG> <STRONG>short</STRONG> <EM>pair</EM><STRONG>,</STRONG> <STRONG>void</STRONG> <STRONG>*</STRONG><EM>opts</EM><STRONG>);</STRONG>
<STRONG>int</STRONG> <STRONG>mvcur(int</STRONG> <EM>oldrow</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>oldcol</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>newrow</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>newcol</EM><STRONG>);</STRONG>
<STRONG>int</STRONG> <STRONG>tigetflag(const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>cap-code</EM><STRONG>);</STRONG>
<STRONG>int</STRONG> <STRONG>tigetnum(const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>cap-code</EM><STRONG>);</STRONG>
<STRONG>char</STRONG> <STRONG>*tigetstr(const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>cap-code</EM><STRONG>);</STRONG>
<STRONG>char</STRONG> <STRONG>*tiparm(const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>str</EM><STRONG>,</STRONG> ...<STRONG>);</STRONG>
<EM>/*</EM> <EM>extensions</EM> <EM>*/</EM>
<STRONG>char</STRONG> <STRONG>*tiparm_s(int</STRONG> <EM>expected</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>mask</EM><STRONG>,</STRONG> <STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>str</EM><STRONG>,</STRONG> <STRONG>...);</STRONG>
<STRONG>int</STRONG> <STRONG>tiscan_s(int</STRONG> <STRONG>*</STRONG><EM>expected</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <STRONG>*</STRONG><EM>mask</EM><STRONG>,</STRONG> <STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>str</EM><STRONG>);</STRONG>
<EM>/*</EM> <EM>deprecated</EM> <EM>*/</EM>
<STRONG>int</STRONG> <STRONG>setterm(const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>term</EM><STRONG>);</STRONG>
</PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
These low-level functions must be called by programs that deal directly
with the <EM>terminfo</EM> database to handle certain terminal capabilities,
such as programming function keys. For all other functionality, <EM>curses</EM>
functions are more suitable and their use is recommended.
None of these functions use (or are aware of) multibyte character
strings such as UTF-8.
<STRONG>o</STRONG> Capability names and codes use the POSIX portable character set.
<STRONG>o</STRONG> Capability string values have no associated encoding; they are
strings of 8-bit characters.
</PRE><H3><a name="h3-Initialization">Initialization</a></H3><PRE>
Initially, <STRONG>setupterm</STRONG> should be called. The high-level <EM>curses</EM> functions
<STRONG>initscr</STRONG> and <STRONG>newterm</STRONG> call <STRONG>setupterm</STRONG> to initialize the low-level set of
terminal-dependent variables listed in <STRONG><A HREF="term_variables.3x.html">term_variables(3x)</A></STRONG>.
Applications can use the terminal capabilities either directly (via
header definitions), or by special functions. The header files
<EM>curses.h</EM> and <EM>term.h</EM> should be included (in that order) to get the
definitions for these strings, numbers, and flags.
The <EM>terminfo</EM> variables <STRONG>lines</STRONG> and <STRONG>columns</STRONG> are initialized by <STRONG>setupterm</STRONG>
as follows.
<STRONG>o</STRONG> If <STRONG>use_env(FALSE)</STRONG> has been called, values for <STRONG>lines</STRONG> and <STRONG>columns</STRONG>
specified in <EM>terminfo</EM> are used.
<STRONG>o</STRONG> Otherwise, if the environment variables <EM>LINES</EM> and <EM>COLUMNS</EM> exist,
their values are used. If these environment variables do not exist
and the program is running in a window, the current window size is
used. Otherwise, if the environment variables do not exist, the
values for <STRONG>lines</STRONG> and <STRONG>columns</STRONG> specified in the <EM>terminfo</EM> database are
used.
Parameterized strings should be passed through <STRONG>tparm</STRONG> to instantiate
them. All <EM>terminfo</EM> strings (including the output of <STRONG>tparm</STRONG>) should be
sent to the terminal device with <STRONG>tputs</STRONG> or <STRONG>putp</STRONG>. Call <STRONG>reset_shell_mode</STRONG>
to restore the terminal modes before exiting; see <STRONG><A HREF="curs_kernel.3x.html">curs_kernel(3x)</A></STRONG>.
Programs that use cursor addressing should
<STRONG>o</STRONG> output <STRONG>enter_ca_mode</STRONG> upon startup and
<STRONG>o</STRONG> output <STRONG>exit_ca_mode</STRONG> before exiting.
Programs that execute shell subprocesses should
<STRONG>o</STRONG> call <STRONG>reset_shell_mode</STRONG> and output <STRONG>exit_ca_mode</STRONG> before the shell is
called and
<STRONG>o</STRONG> output <STRONG>enter_ca_mode</STRONG> and call <STRONG>reset_prog_mode</STRONG> after returning from
the shell.
<STRONG>setupterm</STRONG> reads in the <EM>terminfo</EM> database, initializing the <EM>terminfo</EM>
structures, but does not set up the output virtualization structures
used by <EM>curses</EM>. Its parameters follow.
<EM>term</EM> is the terminal type, a character string. If <EM>term</EM> is null, the
environment variable <EM>TERM</EM> is read.
<EM>filedes</EM>
is the file descriptor used for getting and setting terminal
I/O modes.
Higher-level applications use <STRONG><A HREF="curs_initscr.3x.html">newterm(3x)</A></STRONG> to initialize the
terminal, passing an output <EM>stream</EM> rather than a <EM>descriptor</EM>.
In <EM>curses</EM>, the two are the same because <STRONG>newterm</STRONG> calls
<STRONG>setupterm</STRONG>, passing the file descriptor derived from its output
stream parameter.
<EM>errret</EM>
points to an optional location where an error status can be
returned to the caller. If <EM>errret</EM> is not null, then <STRONG>setupterm</STRONG>
returns <STRONG>OK</STRONG> or <STRONG>ERR</STRONG> and stores a status value in the integer
pointed to by <EM>errret</EM>. A return value of <STRONG>OK</STRONG> combined with
status of <STRONG>1</STRONG> in <EM>errret</EM> is normal.
If <STRONG>ERR</STRONG> is returned, examine <EM>errret:</EM>
<STRONG>1</STRONG> means that the terminal is hardcopy, and cannot be used
for <EM>curses</EM> applications.
<STRONG>setupterm</STRONG> determines if the entry is a hardcopy type by
checking the <STRONG>hardcopy</STRONG> (<STRONG>hc</STRONG>) capability.
<STRONG>0</STRONG> means that the terminal could not be found, or that it is
a generic type, having too little information for <EM>curses</EM>
applications to run.
<STRONG>setupterm</STRONG> determines if the entry is a generic type by
checking the <STRONG>generic_type</STRONG> (<STRONG>gn</STRONG>) capability.
<STRONG>-1</STRONG> means that the <EM>terminfo</EM> database could not be found.
If <EM>errret</EM> is null, <STRONG>setupterm</STRONG> reports an error message upon
finding an error and exits. Thus, the simplest call is:
setupterm((char *)0, 1, (int *)0);
which uses all the defaults and sends the output to <STRONG>stdout</STRONG>.
</PRE><H3><a name="h3-The-Terminal-State">The Terminal State</a></H3><PRE>
<STRONG>setupterm</STRONG> stores its information about the terminal in a <EM>TERMINAL</EM>
structure pointed to by the global variable <STRONG>cur_term</STRONG>. If it detects an
error, or decides that the terminal is unsuitable (hardcopy or
generic), it discards this information, making it not available to
applications.
If <STRONG>setupterm</STRONG> is called repeatedly for the same terminal type, it will
reuse the information. It maintains only one copy of a given
terminal's capabilities in memory. If it is called for different
terminal types, <STRONG>setupterm</STRONG> allocates new storage for each set of
terminal capabilities.
<STRONG>set_curterm</STRONG> sets <STRONG>cur_term</STRONG> to <EM>nterm</EM>, and makes all of the <EM>terminfo</EM>
Boolean, numeric, and string variables use the values from <EM>nterm</EM>. It
returns the old value of <STRONG>cur_term</STRONG>.
<STRONG>del_curterm</STRONG> frees the space pointed to by <EM>oterm</EM> and makes it available
for further use. If <EM>oterm</EM> is the same as <STRONG>cur_term</STRONG>, references to any
of the <EM>terminfo</EM> Boolean, numeric, and string variables thereafter may
refer to invalid memory locations until another <STRONG>setupterm</STRONG> has been
called.
<STRONG>restartterm</STRONG> is similar to <STRONG>setupterm</STRONG> and <STRONG>initscr</STRONG>, except that it is
called after restoring memory to a previous state (for example, when
reloading a game saved as a core image dump). <STRONG>restartterm</STRONG> assumes that
the windows and the input and output options are the same as when
memory was saved, but the terminal type and baud rate may be different.
Accordingly, <STRONG>restartterm</STRONG> saves various terminal state bits, calls
<STRONG>setupterm</STRONG>, and then restores the bits.
</PRE><H3><a name="h3-Formatting-Output">Formatting Output</a></H3><PRE>
<STRONG>tparm</STRONG> instantiates the string <EM>str</EM> with parameters <EM>pi</EM>. A pointer is
returned to the result of <EM>str</EM> with the parameters applied. Application
developers should keep in mind these quirks of the interface:
<STRONG>o</STRONG> Although <STRONG>tparm</STRONG>'s actual parameters may be integers or strings, the
prototype expects <EM>long</EM> (integer) values.
<STRONG>o</STRONG> Aside from the <STRONG>set_attributes</STRONG> (<STRONG>sgr</STRONG>) capability, most terminal
capabilities require no more than one or two parameters.
<STRONG>o</STRONG> Padding information is ignored by <STRONG>tparm</STRONG>; it is interpreted by
<STRONG>tputs</STRONG>.
<STRONG>o</STRONG> The capability string is null-terminated. Use "\200" where an
ASCII NUL is needed in the output.
<STRONG>tiparm</STRONG> is a newer form of <STRONG>tparm</STRONG> which uses <EM>stdarg.h</EM> rather than a
fixed-parameter list. Its numeric parameters are <EM>int</EM>s rather than
<EM>long</EM>s.
Both <STRONG>tparm</STRONG> and <STRONG>tiparm</STRONG> assume that the application passes parameters
consistent with the terminal description. Two extensions are provided
as alternatives to deal with untrusted data.
<STRONG>o</STRONG> <STRONG>tiparm_s</STRONG> is an extension which is a safer formatting function than
<STRONG>tparm</STRONG> or <STRONG>tiparm</STRONG>, because it allows the developer to tell the <EM>curses</EM>
library how many parameters to expect in the parameter list, and
which may be string parameters.
The <EM>mask</EM> parameter has one bit set for each of the parameters (up
to 9) passed as <EM>char</EM> pointers rather than numbers.
<STRONG>o</STRONG> The extension <STRONG>tiscan_s</STRONG> allows the application to inspect a
formatting capability to see what the <EM>curses</EM> library would assume.
</PRE><H3><a name="h3-Output-Functions">Output Functions</a></H3><PRE>
String capabilities can contain padding information, a time delay
(accommodating performance limitations of hardware terminals) expressed
as <STRONG>$&lt;</STRONG><EM>n</EM><STRONG>&gt;</STRONG>, where <EM>n</EM> is a nonnegative integral count of milliseconds. If <EM>n</EM>
exceeds 30,000 (thirty seconds), it is capped at that value.
<STRONG>tputs</STRONG> interprets time-delay information in the string <EM>str</EM> and outputs
it, executing the delays:
<STRONG>o</STRONG> The <EM>str</EM> parameter must be a <EM>terminfo</EM> string variable or the return
value of <STRONG>tparm</STRONG>, <STRONG>tiparm</STRONG>, <STRONG>tgetstr</STRONG>, or <STRONG>tgoto</STRONG>.
The <STRONG>tgetstr</STRONG> and <STRONG>tgoto</STRONG> functions are part of the <EM>termcap</EM> interface,
which happens to share these function names with the <EM>terminfo</EM> API.
<STRONG>o</STRONG> <EM>affcnt</EM> is the number of lines affected, or <STRONG>1</STRONG> if not applicable.
<STRONG>o</STRONG> <EM>putc</EM> is a <EM>putchar</EM>-like function to which the characters are passed,
one at a time.
If <STRONG>tputs</STRONG> processes a time-delay, it uses the <STRONG><A HREF="curs_util.3x.html">delay_output(3x)</A></STRONG>
function, routing any resulting padding characters through this
function.
<STRONG>putp</STRONG> calls "<STRONG>tputs(</STRONG><EM>str</EM><STRONG>,</STRONG> <STRONG>1,</STRONG> <STRONG>putchar)</STRONG>". The output of <STRONG>putp</STRONG> always goes to
<STRONG>stdout</STRONG>, rather than the <EM>filedes</EM> specified in <STRONG>setupterm</STRONG>.
<STRONG>vidputs</STRONG> displays the string on the terminal in the video attribute mode
<EM>attrs</EM>, which is any combination of the attributes listed in <STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG>.
The characters are passed to the <EM>putchar</EM>-like function <EM>putc</EM>.
<STRONG>vidattr</STRONG> is like <STRONG>vidputs</STRONG>, except that it outputs through <STRONG>putchar(3)</STRONG>.
<STRONG>vid_attr</STRONG> and <STRONG>vid_puts</STRONG> correspond to <STRONG>vidattr</STRONG> and <STRONG>vidputs</STRONG>, respectively.
They use multiple parameters to represent the character attributes and
color; namely,
<STRONG>o</STRONG> <EM>attrs</EM>, of type <EM>attr</EM><STRONG>_</STRONG><EM>t</EM>, for the attributes and
<STRONG>o</STRONG> <EM>pair</EM>, of type <EM>short</EM>, for the color pair number.
Use the attribute constants prefixed with "<STRONG>WA_</STRONG>" with <STRONG>vid_attr</STRONG> and
<STRONG>vid_puts</STRONG>.
X/Open Curses reserves the <EM>opts</EM> argument for future use, saying that
applications must provide a null pointer for that argument; but see
section "EXTENSIONS" below.
<STRONG>mvcur</STRONG> provides low-level cursor motion. It takes effect immediately
(rather than at the next refresh). Unlike the other low-level output
functions, which either write to the standard output or pass an output
function parameter, <STRONG>mvcur</STRONG> uses an output file descriptor derived from
the output stream parameter of <STRONG><A HREF="curs_initscr.3x.html">newterm(3x)</A></STRONG>.
While <STRONG>putp</STRONG> and <STRONG>mvcur</STRONG> are low-level functions that do not use high-level
<EM>curses</EM> state, <EM>ncurses</EM> declares them in <EM>curses.h</EM> because System V did
this (see section "HISTORY" below).
</PRE><H3><a name="h3-Terminal-Capability-Functions">Terminal Capability Functions</a></H3><PRE>
<STRONG>tigetflag</STRONG>, <STRONG>tigetnum</STRONG>, and <STRONG>tigetstr</STRONG> return the value of the capability
corresponding to the <EM>terminfo</EM> <EM>cap-code</EM>, such as <STRONG>xenl</STRONG>, passed to them.
The <EM>cap-code</EM> for each capability is given in the table column entitled
<EM>cap-code</EM> code in the capabilities section of <STRONG><A HREF="terminfo.5.html">terminfo(5)</A></STRONG>.
These functions return special values to denote errors.
<STRONG>tigetflag</STRONG> returns
<STRONG>-1</STRONG> if <EM>cap-code</EM> is not a Boolean capability, or
<STRONG>0</STRONG> if it is canceled or absent from the terminal description.
<STRONG>tigetnum</STRONG> returns
<STRONG>-2</STRONG> if <EM>cap-code</EM> is not a numeric capability, or
<STRONG>-1</STRONG> if it is canceled or absent from the terminal description.
<STRONG>tigetstr</STRONG> returns
<STRONG>(char</STRONG> <STRONG>*)-1</STRONG>
if <EM>cap-code</EM> is not a string capability, or
<STRONG>0</STRONG> if it is canceled or absent from the terminal description.
</PRE><H3><a name="h3-Terminal-Capability-Names">Terminal Capability Names</a></H3><PRE>
These null-terminated arrays contain
<STRONG>o</STRONG> the short <EM>terminfo</EM> names ("codes"),
<STRONG>o</STRONG> the <EM>termcap</EM> names ("names"), and
<STRONG>o</STRONG> the long <EM>terminfo</EM> names ("fnames")
for each of the predefined <EM>terminfo</EM> variables:
<STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*boolnames[]</STRONG>, <STRONG>*boolcodes[]</STRONG>, <STRONG>*boolfnames[]</STRONG>
<STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*numnames[]</STRONG>, <STRONG>*numcodes[]</STRONG>, <STRONG>*numfnames[]</STRONG>
<STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*strnames[]</STRONG>, <STRONG>*strcodes[]</STRONG>, <STRONG>*strfnames[]</STRONG>
</PRE><H3><a name="h3-Releasing-Memory">Releasing Memory</a></H3><PRE>
Each successful call to <STRONG>setupterm</STRONG> allocates memory to hold the terminal
description. As a side effect, it sets <STRONG>cur_term</STRONG> to point to this
memory. If an application calls
del_curterm(cur_term);
the memory will be freed.
The formatting functions <STRONG>tparm</STRONG> and <STRONG>tiparm</STRONG> extend the storage allocated
by <STRONG>setupterm</STRONG> as follows.
<STRONG>o</STRONG> They add the "static" <EM>terminfo</EM> variables [a-z]. Before <EM>ncurses</EM>
6.3, those were shared by all screens. With <EM>ncurses</EM> 6.3, those are
allocated per screen. See <STRONG><A HREF="terminfo.5.html">terminfo(5)</A></STRONG>.
<STRONG>o</STRONG> To improve performance, <EM>ncurses</EM> 6.3 caches the result of analyzing
<EM>terminfo</EM> strings for their parameter types. That is stored as a
binary tree referenced from the <EM>TERMINAL</EM> structure.
The higher-level <STRONG>initscr</STRONG> and <STRONG>newterm</STRONG> functions use <STRONG>setupterm</STRONG>. Normally
they do not free this memory, but it is possible to do that using the
<STRONG><A HREF="curs_initscr.3x.html">delscreen(3x)</A></STRONG> function.
</PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
X/Open Curses defines no failure conditions. In <EM>ncurses</EM>,
<STRONG>del_curtem</STRONG>
fails if its terminal parameter is null.
<STRONG>putp</STRONG> calls <STRONG>tputs</STRONG>, returning the same error codes.
<STRONG>restartterm</STRONG>
fails if the associated call to <STRONG>setupterm</STRONG> returns an error.
<STRONG>setupterm</STRONG>
fails if it cannot allocate enough memory, or create the initial
windows (<STRONG>stdscr</STRONG>, <STRONG>curscr</STRONG>, and <STRONG>newscr</STRONG>) Other error conditions are
documented above.
<STRONG>tparm</STRONG>
returns a null pointer if the capability would require unexpected
parameters; that is, too many, too few, or incorrect types
(strings where integers are expected, or vice versa).
<STRONG>tputs</STRONG>
fails if the string parameter is null. It does not detect I/O
errors: X/Open Curses states that <STRONG>tputs</STRONG> ignores the return value
of the output function <EM>putc</EM>.
</PRE><H2><a name="h2-NOTES">NOTES</a></H2><PRE>
The <STRONG>vid_attr</STRONG> function in <EM>ncurses</EM> is a special case. It was originally
implemented based on a draft of X/Open Curses, as a macro, before other
parts of the <EM>ncurses</EM> wide-character API were developed, and unlike the
other wide-character functions, is also provided in the non-wide-
character configuration.
</PRE><H2><a name="h2-EXTENSIONS">EXTENSIONS</a></H2><PRE>
The functions marked as extensions were designed for <EM>ncurses</EM>, and are
not found in SVr4 <EM>curses</EM>, 4.4BSD <EM>curses</EM>, or any other previous <EM>curses</EM>
implementation.
<EM>ncurses</EM> allows <EM>opts</EM> to be a pointer to <EM>int</EM>, which overrides the <EM>pair</EM>
(<EM>short</EM>) argument.
</PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
<STRONG>setterm</STRONG> is not described by X/Open and must be considered non-portable.
All other functions are as described by X/Open.
</PRE><H3><a name="h3-Compatibility-Macros">Compatibility Macros</a></H3><PRE>
This implementation provides a few macros for compatibility with
systems before SVr4 (see section "HISTORY" below). They include
<STRONG>Bcrmode</STRONG>, <STRONG>Bfixterm</STRONG>, <STRONG>Bgettmode</STRONG>, <STRONG>Bnocrmode</STRONG>, <STRONG>Bresetterm</STRONG>, <STRONG>Bsaveterm</STRONG>, and
<STRONG>Bsetterm</STRONG>.
In SVr4, these are found in <EM>curses.h</EM>, but except for <STRONG>setterm</STRONG>, are
likewise macros. The one function, <STRONG>setterm</STRONG>, is mentioned in the manual
page. It further notes that <STRONG>setterm</STRONG> was replaced by <STRONG>setupterm</STRONG>, stating
that the call
setupterm(<EM>term</EM>, 1, (int *)0)
provides the same functionality as <STRONG>setterm(</STRONG><EM>term</EM><STRONG>)</STRONG>, discouraging the
latter for new programs. <EM>ncurses</EM> implements each of these symbols as
macros for BSD <EM>curses</EM> compatibility.
</PRE><H3><a name="h3-Legacy-Data">Legacy Data</a></H3><PRE>
<STRONG>setupterm</STRONG> copies the terminal name to the array <STRONG>ttytype</STRONG>. This is not
part of X/Open Curses, but is assumed by some applications.
Other implementions may not declare the capability name arrays. Some
provide them without declaring them. X/Open Curses does not specify
them.
Extended terminal capability names, as defined by "<STRONG>tic</STRONG> <STRONG>-x</STRONG>", are not
stored in the arrays described here.
</PRE><H3><a name="h3-Output-Buffering">Output Buffering</a></H3><PRE>
Older versions of <EM>ncurses</EM> assumed that the file descriptor passed to
<STRONG>setupterm</STRONG> from <STRONG>initscr</STRONG> or <STRONG>newterm</STRONG> uses buffered I/O, and would write to
the corresponding stream. In addition to the limitation that the
terminal was left in block-buffered mode on exit (like System V
<EM>curses</EM>), it was problematic because <EM>ncurses</EM> did not allow a reliable
way to clean up on receiving <STRONG>SIGTSTP</STRONG>.
The current version (ncurses6) uses output buffers managed directly by
<EM>ncurses</EM>. Some of the low-level functions described in this manual page
write to the standard output. They are not signal-safe. The high-
level functions in <EM>ncurses</EM> employ alternate versions of these functions
using the more reliable buffering scheme.
</PRE><H3><a name="h3-Function-Prototypes">Function Prototypes</a></H3><PRE>
The X/Open Curses prototypes are based on the SVr4 <EM>curses</EM> header
declarations, which were defined at the same time the C language was
first standardized in the late 1980s.
<STRONG>o</STRONG> X/Open Curses uses <EM>const</EM> less effectively than a later design
might, sometimes applying it needlessly to values that are already
constant, and in most cases overlooking parameters that normally
would use <EM>const</EM>. Passing <EM>const</EM>-qualified parameters to functions
that do not declare them <EM>const</EM> may prevent the program from
compiling. On the other hand, "writable strings" are an
obsolescent feature.
As an extension, this implementation can be configured to change
the function prototypes to use the <EM>const</EM> keyword. The <EM>ncurses</EM> ABI
6 enables this feature by default.
<STRONG>o</STRONG> X/Open Curses prototypes <STRONG>tparm</STRONG> with a fixed number of parameters,
rather than a variable argument list.
This implementation uses a variable argument list, but can be
configured to use the fixed-parameter list. Portable applications
should provide nine parameters after the format; zeroes are fine
for this purpose.
In response to review comments by Thomas E. Dickey, X/Open Curses
Issue 7 proposed the <STRONG>tiparm</STRONG> function in mid-2009.
While <STRONG>tiparm</STRONG> is always provided in <EM>ncurses</EM>, the older form is only
available as a build-time configuration option. If not specially
configured, <STRONG>tparm</STRONG> is the same as <STRONG>tiparm</STRONG>.
Both forms of <STRONG>tparm</STRONG> have drawbacks:
<STRONG>o</STRONG> Most of the calls to <STRONG>tparm</STRONG> use only one or two parameters. Passing
nine on each call is awkward.
Using <EM>long</EM> for the numeric parameter type is a workaround to make
the parameter use the same amount of stack as a pointer. That
approach dates back to the mid-1980s, before C was standardized.
Since then, there is a standard (and pointers are not required to
fit in a <EM>long</EM>).
<STRONG>o</STRONG> Providing the right number of parameters for a variadic function
such as <STRONG>tiparm</STRONG> can be a problem, in particular for string
parameters. However, only a few <EM>terminfo</EM> capabilities use string
parameters (for instance, the ones used for programmable function
keys).
The <EM>ncurses</EM> library checks usage of these capabilities, and returns
an error if the capability mishandles string parameters. But it
cannot check if a calling program provides strings in the right
places for the <STRONG>tparm</STRONG> calls.
The <STRONG><A HREF="tput.1.html">tput(1)</A></STRONG> program checks its use of these capabilities with a
table, so that it calls <STRONG>tparm</STRONG> correctly.
<STRONG>Special</STRONG> <EM>TERM</EM> <STRONG>treatment</STRONG>
If configured to use the terminal driver, as with the MinGW port,
<STRONG>o</STRONG> <STRONG>setupterm</STRONG> interprets a missing/empty <EM>TERM</EM> variable as the special
value "unknown".
SVr4 <EM>curses</EM> uses the special value "dumb".
The difference between the two is that the former uses the
<STRONG>generic_type</STRONG> (<STRONG>gn</STRONG>) <EM>terminfo</EM> capability, while the latter does not.
A generic terminal is unsuitable for full-screen applications.
<STRONG>o</STRONG> <STRONG>setupterm</STRONG> allows explicit use of the the windows console driver by
checking if <STRONG>$TERM</STRONG> is set to "#win32con" or an abbreviation of that
string.
</PRE><H3><a name="h3-Other-Portability-Issues">Other Portability Issues</a></H3><PRE>
In SVr4, <STRONG>set_curterm</STRONG> returns an <EM>int</EM>, <STRONG>OK</STRONG> or <STRONG>ERR</STRONG>. We have chosen to
implement the X/Open Curses semantics.
In SVr4, the third argument of <STRONG>tputs</STRONG> has the type "<STRONG>int</STRONG> <STRONG>(*putc)(char)</STRONG>".
At least one implementation of X/Open Curses (Solaris) returns a value
other than <STRONG>OK</STRONG> or <STRONG>ERR</STRONG> from <STRONG>tputs</STRONG>. It instead returns the length of the
string, and does no error checking.
X/Open Curses notes that after calling <STRONG>mvcur</STRONG>, the <EM>curses</EM> state may not
match the actual terminal state, and that an application should touch
and refresh the window before resuming normal <EM>curses</EM> calls. Both
<EM>ncurses</EM> and SVr4 <EM>curses</EM> implement <STRONG>mvcur</STRONG> using the <EM>SCREEN</EM> data allocated
in either <STRONG>initscr</STRONG> or <STRONG>newterm</STRONG>. So though it is documented as a <EM>terminfo</EM>
function, <STRONG>mvcur</STRONG> is really a <EM>curses</EM> function that is not well specified.
X/Open Curses states that the old location must be given for <STRONG>mvcur</STRONG> to
accommodate terminals that lack absolute cursor positioning. <EM>ncurses</EM>
allows the caller to use -1 for either or both old coordinates. The -1
tells <EM>ncurses</EM> that the old location is unknown, and that it must use
only absolute motion, as with the <STRONG>cursor_address</STRONG> (<STRONG>cup</STRONG>) capability,
rather than the least costly combination of absolute and relative
motion.
</PRE><H2><a name="h2-HISTORY">HISTORY</a></H2><PRE>
SVr2 (1984) introduced the <EM>terminfo</EM> feature. Its programming manual
mentioned the following low-level functions.
<STRONG>Function</STRONG> <STRONG>Description</STRONG>
------------------------------------------------------------------------
<STRONG>fixterm</STRONG> restore terminal to "in <EM>curses</EM>" state
<STRONG>gettmode</STRONG> establish current terminal modes
<STRONG>mvcur</STRONG> low level cursor motion
<STRONG>putp</STRONG> use <STRONG>tputs</STRONG> to send characters via <EM>putchar</EM>
<STRONG>resetterm</STRONG> set terminal modes to "out of <EM>curses</EM>" state
<STRONG>resetty</STRONG> reset terminal flags to stored value
<STRONG>saveterm</STRONG> save current modes as "in <EM>curses</EM>" state
<STRONG>savetty</STRONG> store current terminal flags
<STRONG>setterm</STRONG> establish terminal with given type
<STRONG>setupterm</STRONG> establish terminal with given type
<STRONG>tparm</STRONG> interpolate parameters into string capability
<STRONG>tputs</STRONG> apply padding information to a string
<STRONG>vidattr</STRONG> like <STRONG>vidputs</STRONG>, but output through <EM>putchar</EM>
<STRONG>vidputs</STRONG> write string to terminal, applying specified attributes
The programming manual also mentioned functions provided for <EM>termcap</EM>
compatibility (commenting that they "may go away at a later date").
<STRONG>Function</STRONG> <STRONG>Description</STRONG>
------------------------------------------------------------------------
<STRONG>tgetent</STRONG> look up <EM>termcap</EM> entry for given <EM>name</EM>
<STRONG>tgetflag</STRONG> get Boolean entry for given <EM>id</EM>
<STRONG>tgetnum</STRONG> get numeric entry for given <EM>id</EM>
<STRONG>tgetstr</STRONG> get string entry for given <EM>id</EM>
<STRONG>tgoto</STRONG> apply parameters to given capability
<STRONG>tputs</STRONG> write characters via a function parameter, applying padding
Early <EM>terminfo</EM> programs obtained capability values from the <EM>TERMINAL</EM>
structure initialized by <STRONG>setupterm</STRONG>.
SVr3 (1987) extended <EM>terminfo</EM> by adding functions to retrieve
capability values (like the <EM>termcap</EM> interface), and reusing <STRONG>tgoto</STRONG> and
<STRONG>tputs</STRONG>.
<STRONG>Function</STRONG> <STRONG>Description</STRONG>
------------------------------------------------------------------------
<STRONG>tigetflag</STRONG> get Boolean entry for given <EM>id</EM>
<STRONG>tigetnum</STRONG> get numeric entry for given <EM>id</EM>
<STRONG>tigetstr</STRONG> get string entry for given <EM>id</EM>
SVr3 also replaced several of the SVr2 <EM>terminfo</EM> functions that had no
counterpart in the <EM>termcap</EM> interface, documenting them as obsolete.
<STRONG>Function</STRONG> <STRONG>Replaced</STRONG> <STRONG>by</STRONG>
------------------------------------------------------------------------
crmode cbreak
fixterm reset_prog_mode
gettmode <EM>n/a</EM>
nocrmode nocbreak
resetterm reset_shell_mode
saveterm def_prog_mode
setterm setupterm
SVr3 kept the <STRONG>mvcur</STRONG>, <STRONG>vidattr</STRONG>, and <STRONG>vidputs</STRONG> functions, along with <STRONG>putp</STRONG>,
<STRONG>tparm</STRONG>, and <STRONG>tputs</STRONG>. The latter were needed to support padding, and to
handle capabilities accessed by functions such as <STRONG>vidattr</STRONG> (which used
more than the two parameters supported by <STRONG>tgoto</STRONG>).
SVr3 introduced the functions for switching between terminal
descriptions; for example, <STRONG>set_curterm</STRONG>. Some changes reflected
incremental improvements to the SVr2 library.
<STRONG>o</STRONG> The <EM>TERMINAL</EM> type definition was introduced in SVr3.01, for the
<EM>term</EM> structure provided in SVr2.
<STRONG>o</STRONG> Various global variables such as <STRONG>boolnames</STRONG> were mentioned in the
programming manual at this point, though the variables had been
provided in SVr2.
SVr4 (1989) added the <STRONG>vid_attr</STRONG> and <STRONG>vid_puts</STRONG> functions.
Other low-level functions are declared in the <EM>curses</EM> header files of
Unix systems, but none are documented. Those noted as "obsolete" by
SVr3 remained in use by System V's <STRONG>vi(1)</STRONG> editor.
</PRE><H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE>
<STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG>, <STRONG><A HREF="curs_initscr.3x.html">curs_initscr(3x)</A></STRONG>, <STRONG><A HREF="curs_kernel.3x.html">curs_kernel(3x)</A></STRONG>, <STRONG><A HREF="curs_memleaks.3x.html">curs_memleaks(3x)</A></STRONG>,
<STRONG><A HREF="curs_termcap.3x.html">curs_termcap(3x)</A></STRONG>, <STRONG><A HREF="curs_variables.3x.html">curs_variables(3x)</A></STRONG>, <STRONG>putc(3)</STRONG>, <STRONG><A HREF="term_variables.3x.html">term_variables(3x)</A></STRONG>,
<STRONG><A HREF="terminfo.5.html">terminfo(5)</A></STRONG>
ncurses 6.5 2024-04-13 <STRONG><A HREF="curs_terminfo.3x.html">curs_terminfo(3x)</A></STRONG>
</PRE>
<div class="nav">
<ul>
<li><a href="#h2-NAME">NAME</a></li>
<li><a href="#h2-SYNOPSIS">SYNOPSIS</a></li>
<li><a href="#h2-DESCRIPTION">DESCRIPTION</a>
<ul>
<li><a href="#h3-Initialization">Initialization</a></li>
<li><a href="#h3-The-Terminal-State">The Terminal State</a></li>
<li><a href="#h3-Formatting-Output">Formatting Output</a></li>
<li><a href="#h3-Output-Functions">Output Functions</a></li>
<li><a href="#h3-Terminal-Capability-Functions">Terminal Capability Functions</a></li>
<li><a href="#h3-Terminal-Capability-Names">Terminal Capability Names</a></li>
<li><a href="#h3-Releasing-Memory">Releasing Memory</a></li>
</ul>
</li>
<li><a href="#h2-RETURN-VALUE">RETURN VALUE</a></li>
<li><a href="#h2-NOTES">NOTES</a></li>
<li><a href="#h2-EXTENSIONS">EXTENSIONS</a></li>
<li><a href="#h2-PORTABILITY">PORTABILITY</a>
<ul>
<li><a href="#h3-Compatibility-Macros">Compatibility Macros</a></li>
<li><a href="#h3-Legacy-Data">Legacy Data</a></li>
<li><a href="#h3-Output-Buffering">Output Buffering</a></li>
<li><a href="#h3-Function-Prototypes">Function Prototypes</a></li>
<li><a href="#h3-Other-Portability-Issues">Other Portability Issues</a></li>
</ul>
</li>
<li><a href="#h2-HISTORY">HISTORY</a></li>
<li><a href="#h2-SEE-ALSO">SEE ALSO</a></li>
</ul>
</div>
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