-<!--
+<!--
****************************************************************************
- * Copyright (c) 1998-2014,2015 Free Software Foundation, Inc. *
+ * Copyright 2018,2020 Thomas E. Dickey *
+ * Copyright 1998-2016,2017 Free Software Foundation, Inc. *
* *
* Permission is hereby granted, free of charge, to any person obtaining a *
* copy of this software and associated documentation files (the *
* sale, use or other dealings in this Software without prior written *
* authorization. *
****************************************************************************
- * @Id: curs_initscr.3x,v 1.23 2015/07/16 09:23:42 tom Exp @
+ * @Id: curs_initscr.3x,v 1.33 2020/10/17 23:20:48 tom Exp @
-->
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN">
<HTML>
<HEAD>
<meta http-equiv="Content-Type" content="text/html; charset=us-ascii">
-<meta name="generator" content="Manpage converted by man2html - see http://invisible-island.net/scripts/readme.html#others_scripts">
-<TITLE>curs_initscr 3x</TITLE>
-<link rev=made href="mailto:bug-ncurses@gnu.org">
+<meta name="generator" content="Manpage converted by man2html - see https://invisible-island.net/scripts/readme.html#others_scripts">
+<TITLE>curs_initscr 3X</TITLE>
+<link rel="author" href="mailto:bug-ncurses@gnu.org">
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
</HEAD>
<BODY>
-<H1 class="no-header">curs_initscr 3x</H1>
+<H1 class="no-header">curs_initscr 3X</H1>
<PRE>
-<STRONG><A HREF="curs_initscr.3x.html">curs_initscr(3x)</A></STRONG> <STRONG><A HREF="curs_initscr.3x.html">curs_initscr(3x)</A></STRONG>
+<B><A HREF="curs_initscr.3X.html">curs_initscr(3X)</A></B> <B><A HREF="curs_initscr.3X.html">curs_initscr(3X)</A></B>
-</PRE>
-<H2><a name="h2-NAME">NAME</a></H2><PRE>
- <STRONG>initscr</STRONG>, <STRONG>newterm</STRONG>, <STRONG>endwin</STRONG>, <STRONG>isendwin</STRONG>, <STRONG>set_term</STRONG>, <STRONG>delscreen</STRONG> -
- <STRONG>curses</STRONG> screen initialization and manipulation routines
+</PRE><H2><a name="h2-NAME">NAME</a></H2><PRE>
+ <B>initscr</B>, <B>newterm</B>, <B>endwin</B>, <B>isendwin</B>, <B>set_term</B>, <B>delscreen</B> - <B>curses</B> screen
+ initialization and manipulation routines
-</PRE>
-<H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
- <STRONG>#include</STRONG> <STRONG><curses.h></STRONG>
+</PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
+ <B>#include</B> <B><curses.h></B>
- <STRONG>WINDOW</STRONG> <STRONG>*initscr(void);</STRONG>
- <STRONG>int</STRONG> <STRONG>endwin(void);</STRONG>
- <STRONG>bool</STRONG> <STRONG>isendwin(void);</STRONG>
- <STRONG>SCREEN</STRONG> <STRONG>*newterm(char</STRONG> <STRONG>*type,</STRONG> <STRONG>FILE</STRONG> <STRONG>*outfd,</STRONG> <STRONG>FILE</STRONG> <STRONG>*infd);</STRONG>
- <STRONG>SCREEN</STRONG> <STRONG>*set_term(SCREEN</STRONG> <STRONG>*new);</STRONG>
- <STRONG>void</STRONG> <STRONG>delscreen(SCREEN*</STRONG> <STRONG>sp);</STRONG>
+ <B>WINDOW</B> <B>*initscr(void);</B>
+ <B>int</B> <B>endwin(void);</B>
+ <B>bool</B> <B>isendwin(void);</B>
-</PRE>
-<H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
+ <B>SCREEN</B> <B>*newterm(const</B> <B>char</B> <B>*</B><I>type</I><B>,</B> <B>FILE</B> <B>*</B><I>outfd</I><B>,</B> <B>FILE</B> <B>*</B><I>infd</I><B>);</B>
+ <B>SCREEN</B> <B>*set_term(SCREEN</B> <B>*</B><I>new</I><B>);</B>
+ <B>void</B> <B>delscreen(SCREEN*</B> <I>sp</I><B>);</B>
-</PRE>
-<H3><a name="h3-initscr">initscr</a></H3><PRE>
- <STRONG>initscr</STRONG> is normally the first <STRONG>curses</STRONG> routine to call when
- initializing a program. A few special routines sometimes
- need to be called before it; these are <STRONG>slk_init</STRONG>, <STRONG>filter</STRONG>,
- <STRONG>ripoffline</STRONG>, <STRONG>use_env</STRONG>. For multiple-terminal applications,
- <STRONG>newterm</STRONG> may be called before <STRONG>initscr</STRONG>.
- The initscr code determines the terminal type and initial-
- izes all <STRONG>curses</STRONG> data structures. <STRONG>initscr</STRONG> also causes the
- first call to <STRONG>refresh</STRONG> to clear the screen. If errors oc-
- cur, <STRONG>initscr</STRONG> writes an appropriate error message to stan-
- dard error and exits; otherwise, a pointer is returned to
- <STRONG>stdscr</STRONG>.
+</PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
+</PRE><H3><a name="h3-initscr">initscr</a></H3><PRE>
+ <B>initscr</B> is normally the first <B>curses</B> routine to call when initializing
+ a program. A few special routines sometimes need to be called before
+ it; these are <B><A HREF="curs_slk.3X.html">slk_init(3X)</A></B>, <B>filter</B>, <B>ripoffline</B>, <B>use_env</B>. For multiple-
+ terminal applications, <B>newterm</B> may be called before <B>initscr</B>.
-</PRE>
-<H3><a name="h3-newterm">newterm</a></H3><PRE>
- A program that outputs to more than one terminal should
- use the <STRONG>newterm</STRONG> routine for each terminal instead of
- <STRONG>initscr</STRONG>. A program that needs to inspect capabilities, so
- it can continue to run in a line-oriented mode if the ter-
- minal cannot support a screen-oriented program, would also
- use <STRONG>newterm</STRONG>. The routine <STRONG>newterm</STRONG> should be called once
- for each terminal. It returns a variable of type <STRONG>SCREEN</STRONG> <STRONG>*</STRONG>
- which should be saved as a reference to that terminal.
- <STRONG>newterm</STRONG>'s arguments are
+ The initscr code determines the terminal type and initializes all <B>curs-</B>
+ <B>es</B> data structures. <B>initscr</B> also causes the first call to <B><A HREF="curscurs_refresh.3X.html">refresh(3X)</A></B>
+ to clear the screen. If errors occur, <B>initscr</B> writes an appropriate
+ error message to standard error and exits; otherwise, a pointer is re-
+ turned to <B>stdscr</B>.
- <STRONG>o</STRONG> the <EM>type</EM> of the terminal to be used in place of <STRONG>$TERM</STRONG>,
- <STRONG>o</STRONG> a file pointer for output to the terminal, and
+</PRE><H3><a name="h3-newterm">newterm</a></H3><PRE>
+ A program that outputs to more than one terminal should use the <B>newterm</B>
+ routine for each terminal instead of <B>initscr</B>. A program that needs to
+ inspect capabilities, so it can continue to run in a line-oriented mode
+ if the terminal cannot support a screen-oriented program, would also
+ use <B>newterm</B>. The routine <B>newterm</B> should be called once for each termi-
+ nal. It returns a variable of type <B>SCREEN</B> <B>*</B> which should be saved as a
+ reference to that terminal. <B>newterm</B>'s arguments are
- <STRONG>o</STRONG> another file pointer for input from the terminal
+ <B>o</B> the <I>type</I> of the terminal to be used in place of <B>$TERM</B>,
- If the <EM>type</EM> parameter is <STRONG>NULL</STRONG>, <STRONG>$TERM</STRONG> will be used.
+ <B>o</B> a file pointer for output to the terminal, and
+ <B>o</B> another file pointer for input from the terminal
-</PRE>
-<H3><a name="h3-endwin">endwin</a></H3><PRE>
- The program must also call <STRONG>endwin</STRONG> for each terminal being
- used before exiting from <STRONG>curses</STRONG>. If <STRONG>newterm</STRONG> is called
- more than once for the same terminal, the first terminal
- referred to must be the last one for which <STRONG>endwin</STRONG> is
- called.
+ If the <I>type</I> parameter is <B>NULL</B>, <B>$TERM</B> will be used.
- A program should always call <STRONG>endwin</STRONG> before exiting or es-
- caping from <STRONG>curses</STRONG> mode temporarily. This routine
- <STRONG>o</STRONG> restores tty modes,
+</PRE><H3><a name="h3-endwin">endwin</a></H3><PRE>
+ The program must also call <B>endwin</B> for each terminal being used before
+ exiting from <B>curses</B>. If <B>newterm</B> is called more than once for the same
+ terminal, the first terminal referred to must be the last one for which
+ <B>endwin</B> is called.
- <STRONG>o</STRONG> moves the cursor to the lower left-hand corner of the
- screen and
+ A program should always call <B>endwin</B> before exiting or escaping from
+ <B>curses</B> mode temporarily. This routine
- <STRONG>o</STRONG> resets the terminal into the proper non-visual mode.
+ <B>o</B> resets colors to correspond with the default color pair 0,
- Calling <STRONG>refresh</STRONG> or <STRONG>doupdate</STRONG> after a temporary escape caus-
- es the program to resume visual mode.
+ <B>o</B> moves the cursor to the lower left-hand corner of the screen,
+ <B>o</B> clears the remainder of the line so that it uses the default col-
+ ors,
-</PRE>
-<H3><a name="h3-isendwin">isendwin</a></H3><PRE>
- The <STRONG>isendwin</STRONG> routine returns <STRONG>TRUE</STRONG> if <STRONG>endwin</STRONG> has been
- called without any subsequent calls to <STRONG>wrefresh</STRONG>, and <STRONG>FALSE</STRONG>
- otherwise.
+ <B>o</B> sets the cursor to normal visibility (see <B><A HREF="curs_kernel.3X.html">curs_set(3X)</A></B>),
+ <B>o</B> stops cursor-addressing mode using the <I>exit</I><B>_</B><I>ca</I><B>_</B><I>mode</I> terminal capa-
+ bility,
-</PRE>
-<H3><a name="h3-set_term">set_term</a></H3><PRE>
- The <STRONG>set_term</STRONG> routine is used to switch between different
- terminals. The screen reference <STRONG>new</STRONG> becomes the new cur-
- rent terminal. The previous terminal is returned by the
- routine. This is the only routine which manipulates
- <STRONG>SCREEN</STRONG> pointers; all other routines affect only the cur-
- rent terminal.
+ <B>o</B> restores tty modes (see <B><A HREF="curs_kernel.3X.html">reset_shell_mode(3X)</A></B>).
+ Calling <B><A HREF="curs_refresh.3X.html">refresh(3X)</A></B> or <B><A HREF="curs_refresh.3X.html">doupdate(3X)</A></B> after a temporary escape causes the
+ program to resume visual mode.
-</PRE>
-<H3><a name="h3-delscreen">delscreen</a></H3><PRE>
- The <STRONG>delscreen</STRONG> routine frees storage associated with the
- <STRONG>SCREEN</STRONG> data structure. The <STRONG>endwin</STRONG> routine does not do
- this, so <STRONG>delscreen</STRONG> should be called after <STRONG>endwin</STRONG> if a par-
- ticular <STRONG>SCREEN</STRONG> is no longer needed.
+</PRE><H3><a name="h3-isendwin">isendwin</a></H3><PRE>
+ The <B>isendwin</B> routine returns <B>TRUE</B> if <B>endwin</B> has been called without any
+ subsequent calls to <B>wrefresh</B>, and <B>FALSE</B> otherwise.
-</PRE>
-<H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
- <STRONG>endwin</STRONG> returns the integer <STRONG>ERR</STRONG> upon failure and <STRONG>OK</STRONG> upon
- successful completion.
- Routines that return pointers always return <STRONG>NULL</STRONG> on error.
+</PRE><H3><a name="h3-set_term">set_term</a></H3><PRE>
+ The <B>set_term</B> routine is used to switch between different terminals.
+ The screen reference <B>new</B> becomes the new current terminal. The previ-
+ ous terminal is returned by the routine. This is the only routine
+ which manipulates <B>SCREEN</B> pointers; all other routines affect only the
+ current terminal.
- X/Open defines no error conditions. In this implementa-
- tion
- <STRONG>o</STRONG> <STRONG>endwin</STRONG> returns an error if the terminal was not ini-
- tialized.
+</PRE><H3><a name="h3-delscreen">delscreen</a></H3><PRE>
+ The <B>delscreen</B> routine frees storage associated with the <B>SCREEN</B> data
+ structure. The <B>endwin</B> routine does not do this, so <B>delscreen</B> should be
+ called after <B>endwin</B> if a particular <B>SCREEN</B> is no longer needed.
- <STRONG>o</STRONG> <STRONG>newterm</STRONG> returns an error if it cannot allocate the da-
- ta structures for the screen, or for the top-level
- windows within the screen, i.e., <STRONG>curscr</STRONG>, <STRONG>newscr</STRONG>, or
- <STRONG>stdscr</STRONG>.
- <STRONG>o</STRONG> <STRONG>set_term</STRONG> returns no error.
+</PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
+ <B>endwin</B> returns the integer <B>ERR</B> upon failure and <B>OK</B> upon successful com-
+ pletion.
+ Routines that return pointers always return <B>NULL</B> on error.
-</PRE>
-<H2><a name="h2-NOTES">NOTES</a></H2><PRE>
- Note that <STRONG>initscr</STRONG> and <STRONG>newterm</STRONG> may be macros.
+ X/Open defines no error conditions. In this implementation
+ <B>o</B> <B>endwin</B> returns an error if the terminal was not initialized.
-</PRE>
-<H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
- These functions were described in the XSI Curses standard,
- Issue 4. As of 2015, the current document is X/Open Curs-
- es, Issue 7.
+ <B>o</B> <B>newterm</B> returns an error if it cannot allocate the data structures
+ for the screen, or for the top-level windows within the screen,
+ i.e., <B>curscr</B>, <B>newscr</B>, or <B>stdscr</B>.
+ <B>o</B> <B>set_term</B> returns no error.
-</PRE>
-<H3><a name="h3-Differences">Differences</a></H3><PRE>
- X/Open specifies that portable applications must not call
- <STRONG>initscr</STRONG> more than once:
- <STRONG>o</STRONG> The portable way to use <STRONG>initscr</STRONG> is once only, using
- <STRONG>refresh</STRONG> (see <STRONG><A HREF="curs_refresh.3x.html">curs_refresh(3x)</A></STRONG>) to restore the screen
- after <STRONG>endwin</STRONG>.
+</PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
+ These functions were described in the XSI Curses standard, Issue 4. As
+ of 2015, the current document is X/Open Curses, Issue 7.
- <STRONG>o</STRONG> This implementation allows using <STRONG>initscr</STRONG> after <STRONG>endwin</STRONG>.
- Old versions of curses, e.g., BSD 4.4, may have returned a
- null pointer from <STRONG>initscr</STRONG> when an error is detected,
- rather than exiting. It is safe but redundant to check
- the return value of <STRONG>initscr</STRONG> in XSI Curses.
+</PRE><H3><a name="h3-Differences">Differences</a></H3><PRE>
+ X/Open specifies that portable applications must not call <B>initscr</B> more
+ than once:
+ <B>o</B> The portable way to use <B>initscr</B> is once only, using <B>refresh</B> (see
+ <B><A HREF="curs_refresh.3X.html">curs_refresh(3X)</A></B>) to restore the screen after <B>endwin</B>.
-</PRE>
-<H3><a name="h3-Unset-TERM-Variable">Unset TERM Variable</a></H3><PRE>
- If the TERM variable is missing or empty, <STRONG>initscr</STRONG> uses the
- value "unknown", which normally corresponds to a terminal
- entry with the <EM>generic</EM> (<EM>gn</EM>) capability. Generic entries
- are detected by <STRONG>setupterm</STRONG> (see <STRONG><A HREF="curs_terminfo.3x.html">curs_terminfo(3x)</A></STRONG>) and can-
- not be used for full-screen operation. Other implementa-
- tions may handle a missing/empty TERM variable different-
- ly.
+ <B>o</B> This implementation allows using <B>initscr</B> after <B>endwin</B>.
+ Old versions of curses, e.g., BSD 4.4, may have returned a null pointer
+ from <B>initscr</B> when an error is detected, rather than exiting. It is
+ safe but redundant to check the return value of <B>initscr</B> in XSI Curses.
-</PRE>
-<H3><a name="h3-Signal-Handlers">Signal Handlers</a></H3><PRE>
+
+</PRE><H3><a name="h3-Unset-TERM-Variable">Unset TERM Variable</a></H3><PRE>
+ If the TERM variable is missing or empty, <B>initscr</B> uses the value "un-
+ known", which normally corresponds to a terminal entry with the <I>generic</I>
+ (<I>gn</I>) capability. Generic entries are detected by <B>setupterm</B> (see
+ <B><A HREF="curs_terminfo.3X.html">curs_terminfo(3X)</A></B>) and cannot be used for full-screen operation. Other
+ implementations may handle a missing/empty TERM variable differently.
+
+
+</PRE><H3><a name="h3-Signal-Handlers">Signal Handlers</a></H3><PRE>
Quoting from X/Open Curses, section 3.1.1:
- <EM>Curses</EM> <EM>implementations</EM> <EM>may</EM> <EM>provide</EM> <EM>for</EM> <EM>special</EM> <EM>han-</EM>
- <EM>dling</EM> <EM>of</EM> <EM>the</EM> <EM>SIGINT,</EM> <EM>SIGQUIT</EM> <EM>and</EM> <EM>SIGTSTP</EM> <EM>signals</EM> <EM>if</EM>
- <EM>their</EM> <EM>disposition</EM> <EM>is</EM> <EM>SIG</EM><STRONG>_</STRONG><EM>DFL</EM> <EM>at</EM> <EM>the</EM> <EM>time</EM> <STRONG>initscr()</STRONG> <EM>is</EM>
- <EM>called</EM> <STRONG>...</STRONG>
-
- <EM>Any</EM> <EM>special</EM> <EM>handling</EM> <EM>for</EM> <EM>these</EM> <EM>signals</EM> <EM>may</EM> <EM>remain</EM> <EM>in</EM>
- <EM>effect</EM> <EM>for</EM> <EM>the</EM> <EM>life</EM> <EM>of</EM> <EM>the</EM> <EM>process</EM> <EM>or</EM> <EM>until</EM> <EM>the</EM>
- <EM>process</EM> <EM>changes</EM> <EM>the</EM> <EM>disposition</EM> <EM>of</EM> <EM>the</EM> <EM>signal.</EM>
-
- <EM>None</EM> <EM>of</EM> <EM>the</EM> <EM>Curses</EM> <EM>functions</EM> <EM>are</EM> <EM>required</EM> <EM>to</EM> <EM>be</EM> <EM>safe</EM>
- <EM>with</EM> <EM>respect</EM> <EM>to</EM> <EM>signals</EM> ...
-
- This implementation establishes signal handlers during
- initialization, e.g., <STRONG>initscr</STRONG> or <STRONG>newterm</STRONG>. Applications
- which must handle these signals should set up the corre-
- sponding handlers <EM>after</EM> initializing the library:
-
- <STRONG>SIGINT</STRONG>
- The handler <EM>attempts</EM> to cleanup the screen on exit.
- Although it <EM>usually</EM> works as expected, there are lim-
- itations:
-
- <STRONG>o</STRONG> Walking the <STRONG>SCREEN</STRONG> list is unsafe, since all list
- management is done without any signal blocking.
-
- <STRONG>o</STRONG> On systems which have <STRONG>REENTRANT</STRONG> turned on,
- <STRONG>set_term</STRONG> uses functions which could deadlock or
- misbehave in other ways.
-
- <STRONG>o</STRONG> <STRONG>endwin</STRONG> calls other functions, many of which use
- stdio or other library functions which are clear-
- ly unsafe.
-
- <STRONG>SIGTERM</STRONG>
- This uses the same handler as <STRONG>SIGINT</STRONG>, with the same
- limitations. It is not mentioned in X/Open Curses,
- but is more suitable for this purpose than <STRONG>SIGQUIT</STRONG>
- (which is used in debugging).
-
- <STRONG>SIGTSTP</STRONG>
- This handles the <EM>stop</EM> signal, used in job control.
- When resuming the process, this implementation dis-
- cards pending input with <STRONG>flushinput</STRONG> (see
- <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>), and repaints the screen assuming that
- it has been completely altered. It also updates the
- saved terminal modes with <STRONG>def_shell_mode</STRONG> (see
- <STRONG><A HREF="curs_kernel.3x.html">curs_kernel(3x)</A></STRONG>).
-
- <STRONG>SIGWINCH</STRONG>
- This handles the window-size changes which were ini-
- tially ignored in the standardization efforts. The
- handler sets a (signal-safe) variable which is later
- tested in <STRONG>wgetch</STRONG> (see <STRONG><A HREF="curs_getch.3x.html">curs_getch(3x)</A></STRONG>). If <STRONG>keypad</STRONG> has
- been enabled for the corresponding window, <STRONG>wgetch</STRONG> re-
- turns the key symbol <STRONG>KEY_RESIZE</STRONG>. At the same time,
- <STRONG>wgetch</STRONG> calls <STRONG>resizeterm</STRONG> to adjust the standard screen
- <STRONG>stdscr</STRONG>, and update other data such as <STRONG>LINES</STRONG> and <STRONG>COLS</STRONG>.
+ <I>Curses</I> <I>implementations</I> <I>may</I> <I>provide</I> <I>for</I> <I>special</I> <I>handling</I> <I>of</I> <I>the</I>
+ <B>SIGINT</B><I>,</I> <B>SIGQUIT</B> <I>and</I> <B>SIGTSTP</B> <I>signals</I> <I>if</I> <I>their</I> <I>disposition</I> <I>is</I>
+ <B>SIG_DFL</B> <I>at</I> <I>the</I> <I>time</I> <B>initscr</B> <I>is</I> <I>called</I> <B>...</B>
+ <I>Any</I> <I>special</I> <I>handling</I> <I>for</I> <I>these</I> <I>signals</I> <I>may</I> <I>remain</I> <I>in</I> <I>effect</I> <I>for</I>
+ <I>the</I> <I>life</I> <I>of</I> <I>the</I> <I>process</I> <I>or</I> <I>until</I> <I>the</I> <I>process</I> <I>changes</I> <I>the</I> <I>disposi-</I>
+ <I>tion</I> <I>of</I> <I>the</I> <I>signal.</I>
-</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_kernel.3x.html">curs_kernel(3x)</A></STRONG>, <STRONG><A HREF="curs_refresh.3x.html">curs_refresh(3x)</A></STRONG>,
- <STRONG><A HREF="curs_slk.3x.html">curs_slk(3x)</A></STRONG>, <STRONG><A HREF="curs_terminfo.3x.html">curs_terminfo(3x)</A></STRONG>, <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>, <STRONG>curs_vari-</STRONG>
- <STRONG><A HREF="curs_variables.3x.html">ables(3x)</A></STRONG>.
+ <I>None</I> <I>of</I> <I>the</I> <I>Curses</I> <I>functions</I> <I>are</I> <I>required</I> <I>to</I> <I>be</I> <I>safe</I> <I>with</I> <I>respect</I>
+ <I>to</I> <I>signals</I> ...
+
+ This implementation establishes signal handlers during initialization,
+ e.g., <B>initscr</B> or <B>newterm</B>. Applications which must handle these signals
+ should set up the corresponding handlers <I>after</I> initializing the li-
+ brary:
+
+ <B>SIGINT</B>
+ The handler <I>attempts</I> to cleanup the screen on exit. Although it
+ <I>usually</I> works as expected, there are limitations:
+
+ <B>o</B> Walking the <B>SCREEN</B> list is unsafe, since all list management
+ is done without any signal blocking.
+
+ <B>o</B> On systems which have <B>REENTRANT</B> turned on, <B>set_term</B> uses func-
+ tions which could deadlock or misbehave in other ways.
+
+ <B>o</B> <B>endwin</B> calls other functions, many of which use stdio or other
+ library functions which are clearly unsafe.
+
+ <B>SIGTERM</B>
+ This uses the same handler as <B>SIGINT</B>, with the same limitations.
+ It is not mentioned in X/Open Curses, but is more suitable for
+ this purpose than <B>SIGQUIT</B> (which is used in debugging).
+
+ <B>SIGTSTP</B>
+ This handles the <I>stop</I> signal, used in job control. When resuming
+ the process, this implementation discards pending input with
+ <B>flushinput</B> (see <B><A HREF="curs_util.3X.html">curs_util(3X)</A></B>), and repaints the screen assuming
+ that it has been completely altered. It also updates the saved
+ terminal modes with <B>def_shell_mode</B> (see <B><A HREF="curs_kernel.3X.html">curs_kernel(3X)</A></B>).
+
+ <B>SIGWINCH</B>
+ This handles the window-size changes which were ignored in the
+ standardization efforts. The handler sets a (signal-safe) vari-
+ able which is later tested in <B>wgetch</B> (see <B><A HREF="curs_getch.3X.html">curs_getch(3X)</A></B>). If
+ <B>keypad</B> has been enabled for the corresponding window, <B>wgetch</B> re-
+ turns the key symbol <B>KEY_RESIZE</B>. At the same time, <B>wgetch</B> calls
+ <B>resizeterm</B> to adjust the standard screen <B>stdscr</B>, and update other
+ data such as <B>LINES</B> and <B>COLS</B>.
+
+
+</PRE><H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE>
+ <B><A HREF="curses.3X.html">curses(3X)</A></B>, <B><A HREF="curs_kernel.3X.html">curs_kernel(3X)</A></B>, <B><A HREF="curs_refresh.3X.html">curs_refresh(3X)</A></B>, <B><A HREF="curs_slk.3X.html">curs_slk(3X)</A></B>, <B>curs_ter-</B>
+ <B><A HREF="curs_terminfo.3X.html">minfo(3X)</A></B>, <B><A HREF="curs_util.3X.html">curs_util(3X)</A></B>, <B><A HREF="curs_variables.3X.html">curs_variables(3X)</A></B>.
- <STRONG><A HREF="curs_initscr.3x.html">curs_initscr(3x)</A></STRONG>
+ <B><A HREF="curs_initscr.3X.html">curs_initscr(3X)</A></B>
</PRE>
<div class="nav">
<ul>
</ul>
</li>
<li><a href="#h2-RETURN-VALUE">RETURN VALUE</a></li>
-<li><a href="#h2-NOTES">NOTES</a></li>
<li><a href="#h2-PORTABILITY">PORTABILITY</a>
<ul>
<li><a href="#h3-Differences">Differences</a></li>
projects / ncurses.git / blobdiff