<!--
* t
****************************************************************************
- * Copyright 2018-2021,2022 Thomas E. Dickey *
+ * Copyright 2018-2023,2024 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_getch.3x,v 1.63 2022/02/12 20:07:45 tom Exp @
+ * @Id: curs_getch.3x,v 1.78 2024/02/17 19:27:03 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 https://invisible-island.net/scripts/readme.html#others_scripts">
-<TITLE>curs_getch 3x</TITLE>
+<TITLE>curs_getch 3x 2024-02-17 ncurses 6.4 Library calls</TITLE>
<link rel="author" href="mailto:bug-ncurses@gnu.org">
</HEAD>
<BODY>
-<H1 class="no-header">curs_getch 3x</H1>
+<H1 class="no-header">curs_getch 3x 2024-02-17 ncurses 6.4 Library calls</H1>
<PRE>
-<STRONG><A HREF="curs_getch.3x.html">curs_getch(3x)</A></STRONG>
<STRONG><A HREF="curs_getch.3x.html">curs_getch(3x)</A></STRONG>
+<STRONG><A HREF="curs_getch.3x.html">curs_getch(3x)</A></STRONG>
Library calls <STRONG><A HREF="curs_getch.3x.html">curs_getch(3x)</A></STRONG>
</PRE><H2><a name="h2-NAME">NAME</a></H2><PRE>
<STRONG>getch</STRONG>, <STRONG>wgetch</STRONG>, <STRONG>mvgetch</STRONG>, <STRONG>mvwgetch</STRONG>, <STRONG>ungetch</STRONG>, <STRONG>has_key</STRONG> - get (or push back)
- characters from <STRONG>curses</STRONG> terminal keyboard
+ characters from <EM>curses</EM> terminal keyboard
</PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
<STRONG>int</STRONG> <STRONG>getch(void);</STRONG>
<STRONG>int</STRONG> <STRONG>wgetch(WINDOW</STRONG> <STRONG>*</STRONG><EM>win</EM><STRONG>);</STRONG>
-
<STRONG>int</STRONG> <STRONG>mvgetch(int</STRONG> <EM>y</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>x</EM><STRONG>);</STRONG>
<STRONG>int</STRONG> <STRONG>mvwgetch(WINDOW</STRONG> <STRONG>*</STRONG><EM>win</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>y</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>x</EM><STRONG>);</STRONG>
<STRONG>int</STRONG> <STRONG>ungetch(int</STRONG> <EM>ch</EM><STRONG>);</STRONG>
- /* extension */
+ <EM>/*</EM> <EM>extension</EM> <EM>*/</EM>
<STRONG>int</STRONG> <STRONG>has_key(int</STRONG> <EM>ch</EM><STRONG>);</STRONG>
</PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
-</PRE><H3><a name="h3-Reading-
characters">Reading characters</a></H3><PRE>
+</PRE><H3><a name="h3-Reading-
Characters">Reading Characters</a></H3><PRE>
The <STRONG>getch</STRONG>, <STRONG>wgetch</STRONG>, <STRONG>mvgetch</STRONG> and <STRONG>mvwgetch</STRONG>, routines read a character from
the window. In no-delay mode, if no input is waiting, the value <STRONG>ERR</STRONG> is
returned. In delay mode, the program waits until the system passes
text through to the program. Depending on the setting of <STRONG>cbreak</STRONG>, this
is after one character (cbreak mode), or after the first newline
- (nocbreak mode). In half-delay mode, the program waits until a charac-
- ter is typed or the specified timeout has been reached.
+ (nocbreak mode). In half-delay mode, the program waits until a
+ character is typed or the specified timeout has been reached.
If <STRONG>echo</STRONG> is enabled, and the window is not a pad, then the character
- will also be echoed into the designated window according to the follow-
- ing rules:
+ will also be echoed into the designated window according to the
+ following rules:
<STRONG>o</STRONG> If the character is the current erase character, left arrow, or
backspace, the cursor is moved one space to the left and that
screen position is erased as if <STRONG>delch</STRONG> had been called.
- <STRONG>o</STRONG> If the character value is any other <STRONG>KEY_</STRONG> define, the user is alert-
- ed with a <STRONG>beep</STRONG> call.
+ <STRONG>o</STRONG> If the character value is any other <STRONG>KEY_</STRONG> define, the user is
+ alerted with a <STRONG>beep</STRONG> call.
<STRONG>o</STRONG> If the character is a carriage-return, and if <STRONG>nl</STRONG> is enabled, it is
translated to a line-feed after echoing.
is read.
-</PRE><H3><a name="h3-Keypad-
mode">Keypad mode</a></H3><PRE>
+</PRE><H3><a name="h3-Keypad-
Mode">Keypad Mode</a></H3><PRE>
If <STRONG>keypad</STRONG> is <STRONG>TRUE</STRONG>, and a function key is pressed, the token for that
function key is returned instead of the raw characters:
<STRONG>o</STRONG> The predefined function keys are listed in <STRONG><curses.h></STRONG> as macros
- with values outside the range of 8-bit characters. Their names be-
- gin with <STRONG>KEY_</STRONG>.
+ with values outside the range of 8-bit characters. Their names
+ begin with <STRONG>KEY_</STRONG>.
- <STRONG>o</STRONG> Other (user-defined) function keys which may be defined using <STRONG>de-</STRONG>
- <STRONG><A HREF="define_key.3x.html">fine_key(3x)</A></STRONG> have no names, but also are expected to have values
+ <STRONG>o</STRONG> Other (user-defined) function keys which may be defined using
+ <STRONG><A HREF="define_key.3x.html">define_key(3x)</A></STRONG> have no names, but also are expected to have values
outside the range of 8-bit characters.
Thus, a variable intended to hold the return value of a function key
must be of short size or larger.
- When a character that could be the beginning of a function key is re-
- ceived (which, on modern terminals, means an escape character), <STRONG>curses</STRONG>
- sets a timer. If the remainder of the sequence does not come in within
- the designated time, the character is passed through; otherwise, the
- function key value is returned. For this reason, many terminals expe-
- rience a delay between the time a user presses the escape key and the
- escape is returned to the program.
+ When a character that could be the beginning of a function key is
+ received (which, on modern terminals, means an escape character),
+ <STRONG>curses</STRONG> sets a timer. If the remainder of the sequence does not come in
+ within the designated time, the character is passed through; otherwise,
+ the function key value is returned. For this reason, many terminals
+ experience a delay between the time a user presses the escape key and
+ the escape is returned to the program.
- In <STRONG>ncurses</STRONG>, the timer normally expires after the value in <STRONG>ESCDELAY</STRONG> (see
+ In <EM>ncurses</EM>, the timer normally expires after the value in <STRONG>ESCDELAY</STRONG> (see
<STRONG><A HREF="curs_variables.3x.html">curs_variables(3x)</A></STRONG>). If <STRONG>notimeout</STRONG> is <STRONG>TRUE</STRONG>, the timer does not expire;
it is an infinite (or very large) value. Because function keys usually
- begin with an escape character, the terminal may appear to hang in no-
- timeout mode after pressing the escape key until another key is
+ begin with an escape character, the terminal may appear to hang in
+ notimeout mode after pressing the escape key until another key is
pressed.
-</PRE><H3><a name="h3-Ungetting-
characters">Ungetting characters</a></H3><PRE>
+</PRE><H3><a name="h3-Ungetting-
Characters">Ungetting Characters</a></H3><PRE>
The <STRONG>ungetch</STRONG> routine places <EM>ch</EM> back onto the input queue to be returned
- by the next call to <STRONG>wgetch</STRONG>. There is just one input queue for all win-
- dows.
+ by the next call to <STRONG>wgetch</STRONG>. There is just one input queue for all
+ windows.
-</PRE><H3><a name="h3-Predefined-
key-codes">Predefined key-codes</a></H3><PRE>
+</PRE><H3><a name="h3-Predefined-
Key-Codes">Predefined Key Codes</a></H3><PRE>
The following special keys are defined in <STRONG><curses.h></STRONG>.
<STRONG>o</STRONG> Except for the special case <STRONG>KEY_RESIZE</STRONG>, it is necessary to enable
<STRONG>keypad</STRONG> for <STRONG>getch</STRONG> to return these codes.
- <STRONG>o</STRONG> Not all of these are necessarily supported on any particular termi-
- nal.
-
- <STRONG>o</STRONG> The naming convention may seem obscure, with some apparent mis-
- spellings (such as "RSUME" for "resume"). The names correspond to
- the long terminfo capability names for the keys, and were defined
- long ago, in the 1980s.
-
- <STRONG>Name</STRONG> <STRONG>Key</STRONG> <STRONG>name</STRONG>
- -------------------------------------------------
- KEY_BREAK Break key
- KEY_DOWN The four arrow keys ...
- KEY_UP
- KEY_LEFT
- KEY_RIGHT
- KEY_HOME Home key (upward+left arrow)
- KEY_BACKSPACE Backspace
- KEY_F0 Function keys; space for 64 keys
- is reserved.
- KEY_F(<EM>n</EM>) For 0 <= <EM>n</EM> <= 63
- KEY_DL Delete line
- KEY_IL Insert line
- KEY_DC Delete character
- KEY_IC Insert char or enter insert mode
- KEY_EIC Exit insert char mode
- KEY_CLEAR Clear screen
- KEY_EOS Clear to end of screen
- KEY_EOL Clear to end of line
- KEY_SF Scroll 1 line forward
- KEY_SR Scroll 1 line backward (reverse)
- KEY_NPAGE Next page
- KEY_PPAGE Previous page
- KEY_STAB Set tab
- KEY_CTAB Clear tab
- KEY_CATAB Clear all tabs
- KEY_ENTER Enter or send
- KEY_SRESET Soft (partial) reset
- KEY_RESET Reset or hard reset
-
- KEY_PRINT Print or copy
- KEY_LL Home down or bottom (lower left)
- KEY_A1 Upper left of keypad
- KEY_A3 Upper right of keypad
- KEY_B2 Center of keypad
- KEY_C1 Lower left of keypad
- KEY_C3 Lower right of keypad
- KEY_BTAB Back tab key
- KEY_BEG Beg(inning) key
- KEY_CANCEL Cancel key
- KEY_CLOSE Close key
- KEY_COMMAND Cmd (command) key
- KEY_COPY Copy key
- KEY_CREATE Create key
- KEY_END End key
- KEY_EXIT Exit key
- KEY_FIND Find key
- KEY_HELP Help key
- KEY_MARK Mark key
- KEY_MESSAGE Message key
- KEY_MOUSE Mouse event occurred
- KEY_MOVE Move key
- KEY_NEXT Next object key
- KEY_OPEN Open key
- KEY_OPTIONS Options key
- KEY_PREVIOUS Previous object key
- KEY_REDO Redo key
- KEY_REFERENCE Ref(erence) key
- KEY_REFRESH Refresh key
- KEY_REPLACE Replace key
- KEY_RESIZE Screen resized
- KEY_RESTART Restart key
- KEY_RESUME Resume key
- KEY_SAVE Save key
- KEY_SBEG Shifted beginning key
- KEY_SCANCEL Shifted cancel key
- KEY_SCOMMAND Shifted command key
- KEY_SCOPY Shifted copy key
- KEY_SCREATE Shifted create key
- KEY_SDC Shifted delete char key
- KEY_SDL Shifted delete line key
- KEY_SELECT Select key
- KEY_SEND Shifted end key
- KEY_SEOL Shifted clear line key
- KEY_SEXIT Shifted exit key
- KEY_SFIND Shifted find key
- KEY_SHELP Shifted help key
- KEY_SHOME Shifted home key
- KEY_SIC Shifted insert key
- KEY_SLEFT Shifted left arrow key
- KEY_SMESSAGE Shifted message key
- KEY_SMOVE Shifted move key
- KEY_SNEXT Shifted next key
- KEY_SOPTIONS Shifted options key
- KEY_SPREVIOUS Shifted prev key
- KEY_SPRINT Shifted print key
- KEY_SREDO Shifted redo key
- KEY_SREPLACE Shifted replace key
- KEY_SRIGHT Shifted right arrow key
- KEY_SRSUME Shifted resume key
- KEY_SSAVE Shifted save key
- KEY_SSUSPEND Shifted suspend key
- KEY_SUNDO Shifted undo key
- KEY_SUSPEND Suspend key
- KEY_UNDO Undo key
+ <STRONG>o</STRONG> Not all of these are necessarily supported on any particular
+ terminal.
+
+ <STRONG>o</STRONG> The naming convention may seem obscure, with some apparent
+ misspellings (such as "RSUME" for "resume"). The names correspond
+ to the long terminfo capability names for the keys, and were
+ defined long ago, in the 1980s.
+
+ <STRONG>Name</STRONG> <STRONG>Key</STRONG> <STRONG>name</STRONG>
+ -------------------------------------------------
+ KEY_BREAK Break key
+ KEY_DOWN The four arrow keys ...
+ KEY_UP
+ KEY_LEFT
+ KEY_RIGHT
+ KEY_HOME Home key (upward+left arrow)
+ KEY_BACKSPACE Backspace
+ KEY_F0 Function keys; space for 64 keys
+ is reserved.
+ KEY_F(<EM>n</EM>) For 0 <= <EM>n</EM> <= 63
+ KEY_DL Delete line
+ KEY_IL Insert line
+ KEY_DC Delete character
+ KEY_IC Insert char or enter insert mode
+ KEY_EIC Exit insert char mode
+ KEY_CLEAR Clear screen
+ KEY_EOS Clear to end of screen
+ KEY_EOL Clear to end of line
+ KEY_SF Scroll 1 line forward
+ KEY_SR Scroll 1 line backward (reverse)
+ KEY_NPAGE Next page
+ KEY_PPAGE Previous page
+ KEY_STAB Set tab
+ KEY_CTAB Clear tab
+ KEY_CATAB Clear all tabs
+ KEY_ENTER Enter or send
+ KEY_SRESET Soft (partial) reset
+ KEY_RESET Reset or hard reset
+ KEY_PRINT Print or copy
+
+ KEY_LL Home down or bottom (lower left)
+ KEY_A1 Upper left of keypad
+ KEY_A3 Upper right of keypad
+ KEY_B2 Center of keypad
+ KEY_C1 Lower left of keypad
+ KEY_C3 Lower right of keypad
+ KEY_BTAB Back tab key
+ KEY_BEG Beg(inning) key
+ KEY_CANCEL Cancel key
+ KEY_CLOSE Close key
+ KEY_COMMAND Cmd (command) key
+ KEY_COPY Copy key
+ KEY_CREATE Create key
+ KEY_END End key
+ KEY_EXIT Exit key
+ KEY_FIND Find key
+ KEY_HELP Help key
+ KEY_MARK Mark key
+ KEY_MESSAGE Message key
+ KEY_MOUSE Mouse event occurred
+ KEY_MOVE Move key
+ KEY_NEXT Next object key
+ KEY_OPEN Open key
+ KEY_OPTIONS Options key
+ KEY_PREVIOUS Previous object key
+ KEY_REDO Redo key
+ KEY_REFERENCE Ref(erence) key
+ KEY_REFRESH Refresh key
+ KEY_REPLACE Replace key
+ KEY_RESIZE Screen resized
+ KEY_RESTART Restart key
+ KEY_RESUME Resume key
+ KEY_SAVE Save key
+ KEY_SBEG Shifted beginning key
+ KEY_SCANCEL Shifted cancel key
+ KEY_SCOMMAND Shifted command key
+ KEY_SCOPY Shifted copy key
+ KEY_SCREATE Shifted create key
+ KEY_SDC Shifted delete char key
+ KEY_SDL Shifted delete line key
+ KEY_SELECT Select key
+ KEY_SEND Shifted end key
+ KEY_SEOL Shifted clear line key
+ KEY_SEXIT Shifted exit key
+ KEY_SFIND Shifted find key
+ KEY_SHELP Shifted help key
+ KEY_SHOME Shifted home key
+ KEY_SIC Shifted insert key
+ KEY_SLEFT Shifted left arrow key
+ KEY_SMESSAGE Shifted message key
+ KEY_SMOVE Shifted move key
+ KEY_SNEXT Shifted next key
+ KEY_SOPTIONS Shifted options key
+ KEY_SPREVIOUS Shifted prev key
+ KEY_SPRINT Shifted print key
+ KEY_SREDO Shifted redo key
+ KEY_SREPLACE Shifted replace key
+ KEY_SRIGHT Shifted right arrow key
+ KEY_SRSUME Shifted resume key
+ KEY_SSAVE Shifted save key
+ KEY_SSUSPEND Shifted suspend key
+ KEY_SUNDO Shifted undo key
+ KEY_SUSPEND Suspend key
+ KEY_UNDO Undo key
Keypad is arranged like this:
- +-----+------+-------+
- | <STRONG>A1</STRONG> | <STRONG>up</STRONG> | <STRONG>A3</STRONG> |
- +-----+------+-------+
- |<STRONG>left</STRONG> | <STRONG>B2</STRONG> | <STRONG>right</STRONG> |
- +-----+------+-------+
- | <STRONG>C1</STRONG> | <STRONG>down</STRONG> | <STRONG>C3</STRONG> |
- +-----+------+-------+
+ +-----+------+-------+
+ | <STRONG>A1</STRONG> | <STRONG>up</STRONG> | <STRONG>A3</STRONG> |
+ +-----+------+-------+
+ |<STRONG>left</STRONG> | <STRONG>B2</STRONG> | <STRONG>right</STRONG> |
+ +-----+------+-------+
+ | <STRONG>C1</STRONG> | <STRONG>down</STRONG> | <STRONG>C3</STRONG> |
+ +-----+------+-------+
A few of these predefined values do <EM>not</EM> correspond to a real key:
<STRONG>o</STRONG> <STRONG>KEY_RESIZE</STRONG> is returned when the <STRONG>SIGWINCH</STRONG> signal has been detected
whether or not <STRONG>keypad</STRONG> has been enabled.
<STRONG>o</STRONG> <STRONG>KEY_MOUSE</STRONG> is returned for mouse-events (see <STRONG><A HREF="curs_mouse.3x.html">curs_mouse(3x)</A></STRONG>). This
- code relies upon whether or not <STRONG><A HREF="curs_inopts.3x.html">keypad(3x)</A></STRONG> has been enabled, be-
- cause (e.g., with <STRONG>xterm(1)</STRONG> mouse prototocol) ncurses must read es-
- cape sequences, just like a function key.
+ code relies upon whether or not <STRONG><A HREF="curs_inopts.3x.html">keypad(3x)</A></STRONG> has been enabled,
+ because (e.g., with <STRONG>xterm(1)</STRONG> mouse prototocol) <EM>ncurses</EM> must read
+ escape sequences, just like a function key.
-</PRE><H3><a name="h3-Testing-
key-codes">Testing key-codes</a></H3><PRE>
- The <STRONG>has_key</STRONG> routine takes a key-code value from the above list, and re-
- turns <STRONG>TRUE</STRONG> or <STRONG>FALSE</STRONG> according to whether the current terminal type rec-
- ognizes a key with that value.
+</PRE><H3><a name="h3-Testing-
Key-Codes">Testing Key Codes</a></H3><PRE>
+ The <STRONG>has_key</STRONG> routine takes a key-code value from the above list, and
+ returns <STRONG>TRUE</STRONG> or <STRONG>FALSE</STRONG> according to whether the current terminal type
+ recognizes a key with that value.
The library also supports these extensions:
returns <STRONG>ERR</STRONG> if there is no more room in the FIFO.
<STRONG>wgetch</STRONG>
- returns <STRONG>ERR</STRONG> if the window pointer is null, or if its timeout
- expires without having any data, or if the execution was inter-
- rupted by a signal (<STRONG>errno</STRONG> will be set to <STRONG>EINTR</STRONG>).
+ returns <STRONG>ERR</STRONG>
+
+ <STRONG>o</STRONG> if the window pointer is null, or
+
+ <STRONG>o</STRONG> if its timeout expires without having any data, or
- Functions with a "mv" prefix first perform a cursor movement using
+ <STRONG>o</STRONG> if the execution was interrupted by a signal (<STRONG>errno</STRONG> will be
+ set to <STRONG>EINTR</STRONG>).
+
+ Functions with a "mv" prefix first perform a cursor movement using
<STRONG>wmove</STRONG>, and return an error if the position is outside the window, or if
the window pointer is null.
</PRE><H2><a name="h2-NOTES">NOTES</a></H2><PRE>
- Use of the escape key by a programmer for a single character function
- is discouraged, as it will cause a delay of up to one second while the
+ Use of the escape key by a programmer for a single character function
+ is discouraged, as it will cause a delay of up to one second while the
keypad code looks for a following function-key sequence.
- Some keys may be the same as commonly used control keys, e.g., <STRONG>KEY_EN-</STRONG>
- <STRONG>TER</STRONG> versus control/M, <STRONG>KEY_BACKSPACE</STRONG> versus control/H. Some curses im-
- plementations may differ according to whether they treat these control
- keys specially (and ignore the terminfo), or use the terminfo defini-
- tions. <STRONG>Ncurses</STRONG> uses the terminfo definition. If it says that <STRONG>KEY_EN-</STRONG>
- <STRONG>TER</STRONG> is control/M, <STRONG>getch</STRONG> will return <STRONG>KEY_ENTER</STRONG> when you press control/M.
+ Some keys may be the same as commonly used control keys, e.g.,
+ <STRONG>KEY_ENTER</STRONG> versus control/M, <STRONG>KEY_BACKSPACE</STRONG> versus control/H. Some
+ curses implementations may differ according to whether they treat these
+ control keys specially (and ignore the terminfo), or use the terminfo
+ definitions. <EM>ncurses</EM> uses the terminfo definition. If it says that
+ <STRONG>KEY_ENTER</STRONG> is control/M, <STRONG>getch</STRONG> will return <STRONG>KEY_ENTER</STRONG> when you press
+ control/M.
Generally, <STRONG>KEY_ENTER</STRONG> denotes the character(s) sent by the <EM>Enter</EM> key on
the numeric keypad:
Note that <STRONG>getch</STRONG>, <STRONG>mvgetch</STRONG>, and <STRONG>mvwgetch</STRONG> may be macros.
- Historically, the set of keypad macros was largely defined by the ex-
- tremely function-key-rich keyboard of the AT&T 7300, aka 3B1, aka Sa-
- fari 4. Modern personal computers usually have only a small subset of
- these. IBM PC-style consoles typically support little more than
+ Historically, the set of keypad macros was largely defined by the
+ extremely function-key-rich keyboard of the AT&T 7300, aka 3B1, aka
+ Safari 4. Modern personal computers usually have only a small subset
+ of these. IBM PC-style consoles typically support little more than
<STRONG>KEY_UP</STRONG>, <STRONG>KEY_DOWN</STRONG>, <STRONG>KEY_LEFT</STRONG>, <STRONG>KEY_RIGHT</STRONG>, <STRONG>KEY_HOME</STRONG>, <STRONG>KEY_END</STRONG>, <STRONG>KEY_NPAGE</STRONG>,
<STRONG>KEY_PPAGE</STRONG>, and function keys 1 through 12. The Ins key is usually
mapped to <STRONG>KEY_IC</STRONG>.
+</PRE><H2><a name="h2-EXTENSIONS">EXTENSIONS</a></H2><PRE>
+ <STRONG>has_key</STRONG> was designed for <STRONG><A HREF="ncurses.3x.html">ncurses(3x)</A></STRONG>, and is not found in SVr4 <EM>curses</EM>,
+ 4.4BSD <EM>curses</EM>, or any other previous curses implementation.
+
+
</PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
- The *get* functions are described in the XSI Curses standard, Issue 4.
- They read single-byte characters only. The standard specifies that
- they return <STRONG>ERR</STRONG> on failure, but specifies no error conditions.
-
- The echo behavior of these functions on input of <STRONG>KEY_</STRONG> or backspace
- characters was not specified in the SVr4 documentation. This descrip-
- tion is adopted from the XSI Curses standard.
-
- The behavior of <STRONG>getch</STRONG> and friends in the presence of handled signals is
- unspecified in the SVr4 and XSI Curses documentation. Under historical
- curses implementations, it varied depending on whether the operating
- system's implementation of handled signal receipt interrupts a <STRONG>read(2)</STRONG>
- call in progress or not, and also (in some implementations) depending
- on whether an input timeout or non-blocking mode has been set.
-
- <STRONG>KEY_MOUSE</STRONG> is mentioned in XSI Curses, along with a few related terminfo
- capabilities, but no higher-level functions use the feature. The im-
- plementation in ncurses is an extension.
-
- <STRONG>KEY_RESIZE</STRONG> is an extension first implemented for ncurses. NetBSD curs-
- es later added this extension.
-
- Programmers concerned about portability should be prepared for either
- of two cases: (a) signal receipt does not interrupt <STRONG>getch</STRONG>; (b) signal
- receipt interrupts <STRONG>getch</STRONG> and causes it to return <STRONG>ERR</STRONG> with <STRONG>errno</STRONG> set to
+ Applications employing <EM>ncurses</EM> extensions should condition their use on
+ the visibility of the <STRONG>NCURSES_VERSION</STRONG> preprocessor macro.
+
+ X/Open Curses, Issue 4, Version 2, describes <STRONG>getch</STRONG>, <STRONG>wgetch</STRONG>, <STRONG>mvgetch</STRONG>,
+ <STRONG>mvwgetch</STRONG>, and <STRONG>ungetch</STRONG>. They read single-byte characters only. The
+ standard specifies that they return <STRONG>ERR</STRONG> on failure, but describes no
+ failure conditions.
+
+ The echo behavior of these functions on input of <STRONG>KEY_</STRONG> or backspace
+ characters was not specified in the SVr4 documentation. This
+ description is adapted from X/Open Curses.
+
+ The behavior of <STRONG>getch</STRONG> and friends in the presence of signal handlers is
+ unspecified in the SVr4 documentation and X/Open Curses. Under
+ historical curses implementations, it varied depending on whether the
+ operating system's dispatch of a signal to a handler interrupts a
+ <STRONG>read(2)</STRONG> call in progress or not, and also (in some implementations)
+ whether an input timeout or non-blocking mode has been set.
+
+ <STRONG>KEY_MOUSE</STRONG> is mentioned in X/Open Curses, along with a few related <EM>term-</EM>
+ <EM>info</EM> capabilities, but no higher-level functions use the feature. The
+ implementation in <EM>ncurses</EM> is an extension.
+
+ <STRONG>KEY_RESIZE</STRONG> is an extension first implemented for <EM>ncurses.</EM> NetBSD
+ <EM>curses</EM> later added this extension.
+
+ Programmers concerned about portability should be prepared for either
+ of two cases: (a) signal receipt does not interrupt <STRONG>getch</STRONG>; (b) signal
+ receipt interrupts <STRONG>getch</STRONG> and causes it to return <STRONG>ERR</STRONG> with <STRONG>errno</STRONG> set to
<STRONG>EINTR</STRONG>.
- The <STRONG>has_key</STRONG> function is unique to <STRONG>ncurses</STRONG>. We recommend that any code
+ The <STRONG>has_key</STRONG> function is unique to <EM>ncurses</EM>. We recommend that any code
using it be conditionalized on the <STRONG>NCURSES_VERSION</STRONG> feature macro.
</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_inopts.3x.html">curs_inopts(3x)</A></STRONG>, <STRONG><A HREF="curs_mouse.3x.html">curs_mouse(3x)</A></STRONG>, <STRONG><A HREF="curs_move.3x.html">curs_move(3x)</A></STRONG>, <STRONG>curs_out-</STRONG>
- <STRONG><A HREF="curs_outopts.3x.html">opts(3x)</A></STRONG>, <STRONG><A HREF="curs_refresh.3x.html">curs_refresh(3x)</A></STRONG>, <STRONG><A HREF="curs_variables.3x.html">curs_variables(3x)</A></STRONG>, <STRONG><A HREF="resizeterm.3x.html">resizeterm(3x)</A></STRONG>.
+ <STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG>, <STRONG><A HREF="curs_inopts.3x.html">curs_inopts(3x)</A></STRONG>, <STRONG><A HREF="curs_mouse.3x.html">curs_mouse(3x)</A></STRONG>, <STRONG><A HREF="curs_move.3x.html">curs_move(3x)</A></STRONG>,
+ <STRONG><A HREF="curs_outopts.3x.html">curs_outopts(3x)</A></STRONG>, <STRONG><A HREF="curs_refresh.3x.html">curs_refresh(3x)</A></STRONG>, <STRONG><A HREF="curs_variables.3x.html">curs_variables(3x)</A></STRONG>, <STRONG><A HREF="resizeterm.3x.html">resizeterm(3x)</A></STRONG>
- Comparable functions in the wide-character (ncursesw) library are de-
- scribed in <STRONG><A HREF="curs_get_wch.3x.html">curs_get_wch(3x)</A></STRONG>.
+ Comparable functions in the wide-character (ncursesw) library are
+
described in <STRONG><A HREF="curs_get_wch.3x.html">curs_get_wch(3x)</A></STRONG>.
-
<STRONG><A HREF="curs_getch.3x.html">curs_getch(3x)</A></STRONG>
+
ncurses 6.4 2024-02-17 <STRONG><A HREF="curs_getch.3x.html">curs_getch(3x)</A></STRONG>
</PRE>
<div class="nav">
<ul>
<li><a href="#h2-SYNOPSIS">SYNOPSIS</a></li>
<li><a href="#h2-DESCRIPTION">DESCRIPTION</a>
<ul>
-<li><a href="#h3-Reading-characters">Reading characters</a></li>
-<li><a href="#h3-Keypad-mode">Keypad mode</a></li>
-<li><a href="#h3-Ungetting-characters">Ungetting characters</a></li>
-<li><a href="#h3-Predefined-key-codes">Predefined key-codes</a></li>
-<li><a href="#h3-Testing-key-codes">Testing key-codes</a></li>
+<li><a href="#h3-Reading-Characters">Reading Characters</a></li>
+<li><a href="#h3-Keypad-Mode">Keypad Mode</a></li>
+<li><a href="#h3-Ungetting-Characters">Ungetting Characters</a></li>
+<li><a href="#h3-Predefined-Key-Codes">Predefined Key Codes</a></li>
+<li><a href="#h3-Testing-Key-Codes">Testing Key Codes</a></li>
</ul>
</li>
<li><a href="#h2-RETURN-VALUE">RETURN VALUE</a></li>
<li><a href="#h2-NOTES">NOTES</a></li>
+<li><a href="#h2-EXTENSIONS">EXTENSIONS</a></li>
<li><a href="#h2-PORTABILITY">PORTABILITY</a></li>
<li><a href="#h2-SEE-ALSO">SEE ALSO</a></li>
</ul>
projects / ncurses.git / blobdiff