<!--
****************************************************************************
- * Copyright 2018-2020,2021 Thomas E. Dickey *
+ * Copyright 2018-2021,2022 Thomas E. Dickey *
* Copyright 1998-2016,2017 Free Software Foundation, Inc. *
* *
* Permission is hereby granted, free of charge, to any person obtaining a *
* sale, use or other dealings in this Software without prior written *
* authorization. *
****************************************************************************
- * @Id: curs_terminfo.3x,v 1.79 2021/12/25 21:34:58 tom Exp @
+ * @Id: curs_terminfo.3x,v 1.80 2022/01/01 21:50:06 tom Exp @
+ * ***************************************************************************
+ * ***************************************************************************
* ***************************************************************************
* ***************************************************************************
* ***************************************************************************
<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 memo-
+ ry. If an application calls
+
+ <STRONG>del_curterm(cur_term);</STRONG>
+
+ the memory will be freed.
+
+ The formatting functions <STRONG>tparm</STRONG> and <STRONG>tiparm</STRONG> extend the storage allocated
+ by <STRONG>setupterm</STRONG>:
+
+ <STRONG>o</STRONG> the "static" terminfo variables [a-z]. Before ncurses 6.3, those
+ were shared by all screens. With ncurses 6.3, those are allocated
+ per screen. See <STRONG><A HREF="terminfo.5.html">terminfo(5)</A></STRONG> for details.
+
+ <STRONG>o</STRONG> to improve performance, ncurses 6.3 caches the result of analyzing
+ terminfo strings for their parameter types. That is stored as a
+ binary tree referenced from the <STRONG>TERMINAL</STRONG> 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>
- Routines that return an integer return <STRONG>ERR</STRONG> upon failure and <STRONG>OK</STRONG> (SVr4
- only specifies "an integer value other than <STRONG>ERR</STRONG>") upon successful com-
+ Routines that return an integer return <STRONG>ERR</STRONG> upon failure and <STRONG>OK</STRONG> (SVr4
+ only specifies "an integer value other than <STRONG>ERR</STRONG>") upon successful com-
pletion, unless otherwise noted in the preceding routine descriptions.
Routines that return pointers always return <STRONG>NULL</STRONG> on error.
ditions are documented above.
<STRONG>tputs</STRONG>
- returns an error if the string parameter is null. It does not
- detect I/O errors: X/Open states that <STRONG>tputs</STRONG> ignores the return
+ returns an error if the string parameter is null. It does not
+ detect I/O errors: X/Open states that <STRONG>tputs</STRONG> ignores the return
value of the output function <EM>putc</EM>.
</PRE><H3><a name="h3-Compatibility-macros">Compatibility macros</a></H3><PRE>
- This implementation provides a few macros for compatibility with sys-
+ This implementation provides a few macros for compatibility with sys-
tems before SVr4 (see <EM>HISTORY</EM>). Those include <STRONG>crmode</STRONG>, <STRONG>fixterm</STRONG>,
<STRONG>gettmode</STRONG>, <STRONG>nocrmode</STRONG>, <STRONG>resetterm</STRONG>, <STRONG>saveterm</STRONG>, and <STRONG>setterm</STRONG>.
- In SVr4, those are found in <STRONG><curses.h></STRONG>, but except for <STRONG>setterm</STRONG>, are
+ In SVr4, those are found in <STRONG><curses.h></STRONG>, but except for <STRONG>setterm</STRONG>, are
likewise macros. The one function, <STRONG>setterm</STRONG>, is mentioned in the manual
- page. The manual page notes that the <STRONG>setterm</STRONG> routine was replaced by
+ page. The manual page notes that the <STRONG>setterm</STRONG> routine was replaced by
<STRONG>setupterm</STRONG>, stating that the call:
<STRONG>setupterm(</STRONG><EM>term</EM><STRONG>,</STRONG> <STRONG>1,</STRONG> <STRONG>(int</STRONG> <STRONG>*)0)</STRONG>
provides the same functionality as <STRONG>setterm(</STRONG><EM>term</EM><STRONG>)</STRONG>, and is not recommend-
- ed for new programs. This implementation provides each of those sym-
+ ed for new programs. This implementation provides each of those sym-
bols as macros for BSD compatibility,
fixterm restore tty to "in curses" state
gettmode establish current tty modes
mvcur low level cursor motion
- putp utility function that uses <STRONG>tputs</STRONG> to send char-
+ putp utility function that uses <STRONG>tputs</STRONG> to send char-
acters via <STRONG>putchar</STRONG>.
resetterm set tty modes to "out of curses" state
resetty reset tty flags to stored value
tparm instantiate a string expression with parameters
tputs apply padding information to a string
vidattr like <STRONG>vidputs</STRONG>, but outputs through <STRONG>putchar</STRONG>
- vidputs output a string to put terminal in a specified
+ vidputs output a string to put terminal in a specified
video attribute mode
- The programming manual also mentioned functions provided for termcap
+ The programming manual also mentioned functions provided for termcap
compatibility (commenting that they "may go away at a later date"):
<STRONG>Function</STRONG> <STRONG>Description</STRONG>
tputs apply padding to capability, calling
a function to put characters
- Early terminfo programs obtained capability values from the <STRONG>TERMINAL</STRONG>
+ Early terminfo programs obtained capability values from the <STRONG>TERMINAL</STRONG>
structure initialized by <STRONG>setupterm</STRONG>.
- SVr3 extended terminfo by adding functions to retrieve capability val-
+ SVr3 extended terminfo by adding functions to retrieve capability val-
ues (like the termcap interface), and reusing tgoto and tputs:
<STRONG>Function</STRONG> <STRONG>Description</STRONG>
-------------------------------------------
tigetflag get boolean entry for given <EM>id</EM>
+
tigetnum get numeric entry for given <EM>id</EM>
tigetstr get string entry for given <EM>id</EM>
- SVr3 also replaced several of the SVr2 terminfo functions which had no
+ SVr3 also replaced several of the SVr2 terminfo functions which had no
counterpart in the termcap interface, documenting them as obsolete:
<STRONG>Function</STRONG> <STRONG>Replaced</STRONG> <STRONG>by</STRONG>
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 han-
- dling functions such as <STRONG>vidattr</STRONG> (which used more than the two parame-
+ 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 han-
+ dling functions such as <STRONG>vidattr</STRONG> (which used more than the two parame-
ters supported by <STRONG>tgoto</STRONG>).
- SVr3 introduced the functions for switching between terminal descrip-
+ SVr3 introduced the functions for switching between terminal descrip-
tions, e.g., <STRONG>set_curterm</STRONG>. Some of that was incremental improvements to
the SVr2 library:
- <STRONG>o</STRONG> The <STRONG>TERMINAL</STRONG> type definition was introduced in SVr3.01, for the
+ <STRONG>o</STRONG> The <STRONG>TERMINAL</STRONG> type definition was introduced in SVr3.01, for the
<STRONG>term</STRONG> structure provided in SVr2.
- <STRONG>o</STRONG> The various global variables such as <STRONG>boolnames</STRONG> were mentioned in
- the programming manual at this point, though the variables were
+ <STRONG>o</STRONG> The various global variables such as <STRONG>boolnames</STRONG> were mentioned in
+ the programming manual at this point, though the variables were
provided in SVr2.
SVr4 added the <STRONG>vid_attr</STRONG> and <STRONG>vid_puts</STRONG> functions.
</PRE><H3><a name="h3-Legacy-functions">Legacy functions</a></H3><PRE>
X/Open notes that <STRONG>vidattr</STRONG> and <STRONG>vidputs</STRONG> may be macros.
- The function <STRONG>setterm</STRONG> is not described by X/Open and must be considered
+ The function <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-Legacy-data">Legacy data</a></H3><PRE>
- <STRONG>setupterm</STRONG> copies the terminal name to the array <STRONG>ttytype</STRONG>. This is not
+ <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
+ Other implementions may not declare the capability name arrays. Some
provide them without declaring them. X/Open does not specify them.
Extended terminal capability names, e.g., as defined by <STRONG>tic</STRONG> <STRONG>-x</STRONG>, are not
</PRE><H3><a name="h3-Output-buffering">Output buffering</a></H3><PRE>
- Older versions of <STRONG>ncurses</STRONG> assumed that the file descriptor passed to
+ Older versions of <STRONG>ncurses</STRONG> 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 ter-
- minal was left in block-buffered mode on exit (like System V curses),
- it was problematic because <STRONG>ncurses</STRONG> did not allow a reliable way to
+ the corresponding stream. In addition to the limitation that the ter-
+ minal was left in block-buffered mode on exit (like System V curses),
+ it was problematic because <STRONG>ncurses</STRONG> did not allow a reliable way to
cleanup on receiving SIGTSTP.
- The current version (ncurses6) uses output buffers managed directly by
+ The current version (ncurses6) uses output buffers managed directly by
<STRONG>ncurses</STRONG>. Some of the low-level functions described in this manual page
write to the standard output. They are not signal-safe. The high-lev-
el functions in <STRONG>ncurses</STRONG> use alternate versions of these functions using
</PRE><H3><a name="h3-Function-prototypes">Function prototypes</a></H3><PRE>
The X/Open Curses prototypes are based on the SVr4 curses header decla-
- rations, which were defined at the same time the C language was first
+ rations, which were defined at the same time the C language was first
standardized in the late 1980s.
- <STRONG>o</STRONG> X/Open Curses uses <STRONG>const</STRONG> less effectively than a later design
- might, in some cases applying it needlessly to values are already
- constant, and in most cases overlooking parameters which normally
- would use <STRONG>const</STRONG>. Using constant parameters for functions which do
+ <STRONG>o</STRONG> X/Open Curses uses <STRONG>const</STRONG> less effectively than a later design
+ might, in some cases applying it needlessly to values are already
+ constant, and in most cases overlooking parameters which normally
+ would use <STRONG>const</STRONG>. Using constant parameters for functions which do
not use <STRONG>const</STRONG> may prevent the program from compiling. On the other
hand, <EM>writable</EM> <EM>strings</EM> are an obsolescent feature.
- As an extension, this implementation can be configured to change
- the function prototypes to use the <STRONG>const</STRONG> keyword. The ncurses ABI
+ As an extension, this implementation can be configured to change
+ the function prototypes to use the <STRONG>const</STRONG> keyword. The ncurses ABI
6 enables this feature by default.
- <STRONG>o</STRONG> X/Open Curses prototypes <STRONG>tparm</STRONG> with a fixed number of parameters,
+ <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 con-
- figured to use the fixed-parameter list. Portable applications
- should provide 9 parameters after the format; zeroes are fine for
+ This implementation uses a variable argument list, but can be con-
+ figured to use the fixed-parameter list. Portable applications
+ should provide 9 parameters after the format; zeroes are fine for
this purpose.
- In response to review comments by Thomas E. Dickey, X/Open Curses
+ In response to review comments by Thomas E. Dickey, X/Open Curses
Issue 7 proposed the <STRONG>tiparm</STRONG> function in mid-2009.
</PRE><H3><a name="h3-Special-TERM-treatment">Special TERM treatment</a></H3><PRE>
If configured to use the terminal-driver, e.g., for the MinGW port,
- <STRONG>o</STRONG> <STRONG>setupterm</STRONG> interprets a missing/empty TERM variable as the special
+ <STRONG>o</STRONG> <STRONG>setupterm</STRONG> interprets a missing/empty TERM variable as the special
value "unknown".
- <STRONG>o</STRONG> <STRONG>setupterm</STRONG> allows explicit use of the the windows console driver by
- checking if $TERM is set to "#win32con" or an abbreviation of that
+ <STRONG>o</STRONG> <STRONG>setupterm</STRONG> allows explicit use of the the windows console driver by
+ checking if $TERM 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 System V Release 4, <STRONG>set_curterm</STRONG> has an <STRONG>int</STRONG> return type and returns
+ In System V Release 4, <STRONG>set_curterm</STRONG> has an <STRONG>int</STRONG> return type and returns
<STRONG>OK</STRONG> or <STRONG>ERR</STRONG>. We have chosen to implement the X/Open Curses semantics.
- In System V Release 4, the third argument of <STRONG>tputs</STRONG> has the type <STRONG>int</STRONG>
+ In System V Release 4, 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>/<STRONG>ERR</STRONG> from <STRONG>tputs</STRONG>. That returns the length of the string,
+ At least one implementation of X/Open Curses (Solaris) returns a value
+ other than <STRONG>OK</STRONG>/<STRONG>ERR</STRONG> from <STRONG>tputs</STRONG>. That returns the length of the string,
and does no error-checking.
- X/Open notes that after calling <STRONG>mvcur</STRONG>, the curses state may not match
+ X/Open notes that after calling <STRONG>mvcur</STRONG>, the curses state may not match
the actual terminal state, and that an application should touch and re-
fresh the window before resuming normal curses calls. Both <STRONG>ncurses</STRONG> and
- System V Release 4 curses implement <STRONG>mvcur</STRONG> using the SCREEN data allo-
- cated in either <STRONG>initscr</STRONG> or <STRONG>newterm</STRONG>. So though it is documented as a
- terminfo function, <STRONG>mvcur</STRONG> is really a curses function which is not well
+ System V Release 4 curses implement <STRONG>mvcur</STRONG> using the SCREEN data allo-
+ cated in either <STRONG>initscr</STRONG> or <STRONG>newterm</STRONG>. So though it is documented as a
+ terminfo function, <STRONG>mvcur</STRONG> is really a curses function which is not well
specified.
- X/Open states that the old location must be given for <STRONG>mvcur</STRONG>. This im-
- plementation allows the caller to use -1's for the old ordinates. In
+ X/Open states that the old location must be given for <STRONG>mvcur</STRONG>. This im-
+ plementation allows the caller to use -1's for the old ordinates. In
that case, the old location is unknown.
</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_termcap.3x.html">curs_termcap(3x)</A></STRONG>,
- <STRONG><A HREF="curs_variables.3x.html">curs_variables(3x)</A></STRONG>, <STRONG><A HREF="term_variables.3x.html">term_variables(3x)</A></STRONG>, <STRONG>putc(3)</STRONG>, <STRONG><A HREF="terminfo.5.html">terminfo(5)</A></STRONG>
+ <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><A HREF="term_variables.3x.html">term_variables(3x)</A></STRONG>, <STRONG>putc(3)</STRONG>, <STRONG>ter-</STRONG>
+ <STRONG><A HREF="terminfo.5.html">minfo(5)</A></STRONG>
<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>
projects / ncurses.git / blobdiff