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+<H1 class="no-header">curs_initscr 3x</H1>
<PRE>
-<!-- Manpage converted by man2html 3.0.1 -->
+<STRONG><A HREF="curs_initscr.3x.html">curs_initscr(3x)</A></STRONG> <STRONG><A HREF="curs_initscr.3x.html">curs_initscr(3x)</A></STRONG>
-</PRE>
-<H2>NAME</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>SYNOPSIS</H2><PRE>
- <B>#include</B> <B><curses.h></B>
- <B>WINDOW</B> <B>*initscr(void);</B>
- <B>int</B> <B>endwin(void);</B>
- <B>bool</B> <B>isendwin(void);</B>
- <B>SCREEN</B> <B>*newterm(const</B> <B>char</B> <B>*type,</B> <B>FILE</B> <B>*outfd,</B> <B>FILE</B>
- <B>*infd);</B>
- <B>SCREEN</B> <B>*set_term(SCREEN</B> <B>*new);</B>
- <B>void</B> <B>delscreen(SCREEN*</B> <B>sp);</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>DESCRIPTION</H2><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>slk_init</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>.
-
- The initscr code determines the terminal type and initial-
- izes all <B>curses</B> data structures. <B>initscr</B> also causes the
- first call to <B>refresh</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 returned
- to <B>stdscr</B>.
-
- 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 ter-
- minal cannot support a screen-oriented program, would also
- use <B>newterm</B>. The routine <B>newterm</B> should be called once
- for each terminal. It returns a variable of type <B>SCREEN</B> <B>*</B>
- which should be saved as a reference to that terminal.
- The arguments are the <I>type</I> of the terminal to be used in
- place of <B>$TERM</B>, a file pointer for output to the terminal,
- and another file pointer for input from the terminal (if
- <I>type</I> is <B>NULL</B>, <B>$TERM</B> will be used). 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.
-
- A program should always call <B>endwin</B> before exiting or
- escaping from <B>curses</B> mode temporarily. This routine
- restores tty modes, moves the cursor to the lower left-
- hand corner of the screen and resets the terminal into the
- proper non-visual mode. Calling <B>refresh</B> or <B>doupdate</B> after
- a temporary escape causes the program to resume visual
- mode.
-
- 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.
-
- The <B>set_term</B> routine is used to switch between different
- terminals. The screen reference <B>new</B> becomes the new cur-
- rent terminal. The previous terminal is returned by the
- routine. This is the only routine which manipulates
- <B>SCREEN</B> pointers; all other routines affect only the cur-
- rent terminal.
-
- 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 par-
- ticular <B>SCREEN</B> is no longer needed.
+</PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
+ <STRONG>#include</STRONG> <STRONG><curses.h></STRONG>
+ <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>*</STRONG><EM>type</EM><STRONG>,</STRONG> <STRONG>FILE</STRONG> <STRONG>*</STRONG><EM>outfd</EM><STRONG>,</STRONG> <STRONG>FILE</STRONG> <STRONG>*</STRONG><EM>infd</EM><STRONG>);</STRONG>
+ <STRONG>SCREEN</STRONG> <STRONG>*set_term(SCREEN</STRONG> <STRONG>*</STRONG><EM>new</EM><STRONG>);</STRONG>
+ <STRONG>void</STRONG> <STRONG>delscreen(SCREEN*</STRONG> <EM>sp</EM><STRONG>);</STRONG>
-</PRE>
-<H2>RETURN VALUE</H2><PRE>
- <B>endwin</B> returns the integer <B>ERR</B> upon failure and <B>OK</B> upon
- successful completion.
- Routines that return pointers always return <B>NULL</B> on error.
+</PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
+</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><A HREF="curs_slk.3x.html">slk_init(3x)</A></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>.
-</PRE>
-<H2>NOTES</H2><PRE>
- Note that <B>initscr</B> and <B>newterm</B> may be macros.
+ The initscr code determines the terminal type and initializes all <STRONG>curs-</STRONG>
+ <STRONG>es</STRONG> data structures. <STRONG>initscr</STRONG> also causes the first call to <STRONG><A HREF="curscurs_refresh.3x.html">refresh(3x)</A></STRONG>
+ to clear the screen. If errors occur, <STRONG>initscr</STRONG> writes an appropriate
+ error message to standard error and exits; otherwise, a pointer is re-
+ turned to <STRONG>stdscr</STRONG>.
-</PRE>
-<H2>PORTABILITY</H2><PRE>
- These functions are described in the XSI Curses standard,
- Issue 4. It specifies that portable applications must not
- call <B>initscr</B> more than once.
+</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 terminal cannot support a screen-oriented program, would also
+ use <STRONG>newterm</STRONG>. The routine <STRONG>newterm</STRONG> should be called once for each termi-
+ nal. 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
- 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.
+ <STRONG>o</STRONG> the <EM>type</EM> of the terminal to be used in place of <STRONG>$TERM</STRONG>,
+ <STRONG>o</STRONG> a file pointer for output to the terminal, and
-</PRE>
-<H2>SEE ALSO</H2><PRE>
- <B><A HREF="ncurses.3x.html">curses(3x)</A></B>, <B><A HREF="curs_kernel.3x.html">curs_kernel(3x)</A></B>, <B><A HREF="curs_refresh.3x.html">curs_refresh(3x)</A></B>,
- <B><A HREF="curs_slk.3x.html">curs_slk(3x)</A></B>, <B><A HREF="curs_util.3x.html">curs_util(3x)</A></B>
+ <STRONG>o</STRONG> another file pointer for input from the terminal
+
+ If the <EM>type</EM> parameter is <STRONG>NULL</STRONG>, <STRONG>$TERM</STRONG> will be used.
+
+
+</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.
+
+ A program should always call <STRONG>endwin</STRONG> before exiting or escaping from
+ <STRONG>curses</STRONG> mode temporarily. This routine
+
+ <STRONG>o</STRONG> resets colors to correspond with the default color pair 0,
+
+ <STRONG>o</STRONG> moves the cursor to the lower left-hand corner of the screen,
+
+ <STRONG>o</STRONG> clears the remainder of the line so that it uses the default col-
+ ors,
+
+ <STRONG>o</STRONG> sets the cursor to normal visibility (see <STRONG><A HREF="curs_kernel.3x.html">curs_set(3x)</A></STRONG>),
+
+ <STRONG>o</STRONG> stops cursor-addressing mode using the <EM>exit</EM><STRONG>_</STRONG><EM>ca</EM><STRONG>_</STRONG><EM>mode</EM> terminal capa-
+ bility,
+
+ <STRONG>o</STRONG> restores tty modes (see <STRONG><A HREF="curs_kernel.3x.html">reset_shell_mode(3x)</A></STRONG>).
+
+ Calling <STRONG><A HREF="curs_refresh.3x.html">refresh(3x)</A></STRONG> or <STRONG><A HREF="curs_refresh.3x.html">doupdate(3x)</A></STRONG> after a temporary escape causes the
+ program to resume visual mode.
+
+
+</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.
+
+
+</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 current terminal. The previ-
+ ous terminal is returned by the routine. This is the only routine
+ which manipulates <STRONG>SCREEN</STRONG> pointers; all other routines affect only the
+ current terminal.
+
+
+</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 particular <STRONG>SCREEN</STRONG> is no longer needed.
+
+
+</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 com-
+ pletion.
+
+ Routines that return pointers always return <STRONG>NULL</STRONG> on error.
+
+ X/Open defines no error conditions. In this implementation
+
+ <STRONG>o</STRONG> <STRONG>endwin</STRONG> returns an error if the terminal was not initialized.
+
+ <STRONG>o</STRONG> <STRONG>newterm</STRONG> returns an error if it cannot allocate the data 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-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.
+
+
+</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>.
+
+ <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-Unset-TERM-Variable">Unset TERM Variable</a></H3><PRE>
+ If the TERM variable is missing or empty, <STRONG>initscr</STRONG> uses the value "un-
+ known", 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 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>handling</EM> <EM>of</EM> <EM>the</EM>
+ <STRONG>SIGINT</STRONG><EM>,</EM> <STRONG>SIGQUIT</STRONG> <EM>and</EM> <STRONG>SIGTSTP</STRONG> <EM>signals</EM> <EM>if</EM> <EM>their</EM> <EM>disposition</EM> <EM>is</EM>
+ <STRONG>SIG_DFL</STRONG> <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>disposi-</EM>
+ <EM>tion</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 corresponding handlers <EM>after</EM> initializing the li-
+ brary:
+ <STRONG>SIGINT</STRONG>
+ The handler <EM>attempts</EM> to cleanup the screen on exit. Although it
+ <EM>usually</EM> works as expected, there are limitations:
+ <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 func-
+ tions 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 clearly 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 discards 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 ignored in the
+ standardization efforts. The handler sets a (signal-safe) vari-
+ able 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>.
+</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>curs_ter-</STRONG>
+ <STRONG><A HREF="curs_terminfo.3x.html">minfo(3x)</A></STRONG>, <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>, <STRONG><A HREF="curs_variables.3x.html">curs_variables(3x)</A></STRONG>.
+ <STRONG><A HREF="curs_initscr.3x.html">curs_initscr(3x)</A></STRONG>
</PRE>
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-Man(1) output converted with
-<a href="http://www.oac.uci.edu/indiv/ehood/man2html.html">man2html</a>
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+<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-initscr">initscr</a></li>
+<li><a href="#h3-newterm">newterm</a></li>
+<li><a href="#h3-endwin">endwin</a></li>
+<li><a href="#h3-isendwin">isendwin</a></li>
+<li><a href="#h3-set_term">set_term</a></li>
+<li><a href="#h3-delscreen">delscreen</a></li>
+</ul>
+</li>
+<li><a href="#h2-RETURN-VALUE">RETURN VALUE</a></li>
+<li><a href="#h2-PORTABILITY">PORTABILITY</a>
+<ul>
+<li><a href="#h3-Differences">Differences</a></li>
+<li><a href="#h3-Unset-TERM-Variable">Unset TERM Variable</a></li>
+<li><a href="#h3-Signal-Handlers">Signal Handlers</a></li>
+</ul>
+</li>
+<li><a href="#h2-SEE-ALSO">SEE ALSO</a></li>
+</ul>
+</div>
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