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- * Copyright 2018-2021,2022 Thomas E. Dickey *
+ * Copyright 2018-2022,2023 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_initscr.3x,v 1.39 2022/07/24 15:46:49 tom Exp @
+ * @Id: curs_initscr.3x,v 1.40 2023/06/10 16:50:22 tom Exp @
-->
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<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>*newterm(const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>type</EM><STRONG>,</STRONG> <STRONG>FILE</STRONG> <STRONG>*</STRONG><EM>outf</EM><STRONG>,</STRONG> <STRONG>FILE</STRONG> <STRONG>*</STRONG><EM>inf</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>
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
+ use <STRONG>newterm</STRONG>.
+
+ The routine <STRONG>newterm</STRONG> should be called once for each terminal. It re-
+ turns 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
<STRONG>o</STRONG> the <EM>type</EM> of the terminal to be used in place of <STRONG>$TERM</STRONG>,
- <STRONG>o</STRONG> a file pointer for output to the terminal, and
+ <STRONG>o</STRONG> an output stream connected to the terminal, and
- <STRONG>o</STRONG> another file pointer for input from the terminal
+ <STRONG>o</STRONG> an input stream connected to the terminal
If the <EM>type</EM> parameter is <STRONG>NULL</STRONG>, <STRONG>$TERM</STRONG> will be used.
+ The file descriptor of the output stream is passed to <STRONG><A HREF="curs_terminfo.3x.html">setupterm(3x)</A></STRONG>,
+ which returns a pointer to a <STRONG>TERMINAL</STRONG> structure. <STRONG>newterm</STRONG>'s return val-
+ ue holds a pointer to the <STRONG>TERMINAL</STRONG> structure.
+
</PRE><H3><a name="h3-endwin">endwin</a></H3><PRE>
The program must also call <STRONG>endwin</STRONG> for each terminal being used before
the SVr4 model, deleting only the standard <STRONG>WINDOW</STRONG> structures.
+</PRE><H3><a name="h3-High-level-versus-low-level">High-level versus low-level</a></H3><PRE>
+ Different implementations may disagree regarding the level of some
+ functions. For example, <STRONG>SCREEN</STRONG> (returned by <STRONG>newterm</STRONG>) and <STRONG>TERMINAL</STRONG> (re-
+ turned by <STRONG><A HREF="curs_terminfo.3x.html">setupterm(3x)</A></STRONG>) hold file descriptors for the output stream.
+ If an application switches screens using <STRONG>set_term</STRONG>, or switches termi-
+ nals using <STRONG><A HREF="curs_terminfo.3x.html">set_curterm(3x)</A></STRONG>, applications which use the output file de-
+ scriptor can have different behavior depending on which structure holds
+ the corresponding descriptor.
+
+ For example
+
+ <STRONG>o</STRONG> NetBSD's <STRONG><A HREF="curs_termattrs.3x.html">baudrate(3x)</A></STRONG> function uses the descriptor in <STRONG>TERMINAL</STRONG>.
+ <STRONG>ncurses</STRONG> and SVr4 use the descriptor in <STRONG>SCREEN</STRONG>.
+
+ <STRONG>o</STRONG> NetBSD and <STRONG>ncurses</STRONG> use the descriptor in <STRONG>TERMINAL</STRONG> for terminal I/O
+ modes, e.g., <STRONG><A HREF="curs_kernel.3x.html">def_shell_mode(3x)</A></STRONG>, <STRONG><A HREF="curs_kernel.3x.html">def_prog_mode(3x)</A></STRONG>. SVr4 curses
+ uses the descriptor in <STRONG>SCREEN</STRONG>.
+
+
</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-
+ 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.
+ (<EM>gn</EM>) capability. Generic entries are detected by <STRONG><A HREF="curs_terminfo.3x.html">setupterm(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>
+ <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> ...
- <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>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>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,
+ 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-
+ 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
+ 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
+ <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-
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 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
+ 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
+ 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="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>.
<li><a href="#h2-PORTABILITY">PORTABILITY</a>
<ul>
<li><a href="#h3-Differences">Differences</a></li>
+<li><a href="#h3-High-level-versus-low-level">High-level versus low-level</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>
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