ncurses 6.1 - patch 20180728
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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>&lt;curses.h&gt;</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>&lt;curses.h&gt;</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(const</STRONG> <STRONG>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>
-<HR>
-<ADDRESS>
-Man(1) output converted with
-<a href="http://www.oac.uci.edu/indiv/ehood/man2html.html">man2html</a>
-</ADDRESS>
+<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>
 </BODY>
 </HTML>