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+<H1 class="no-header">curs_getch 3x 2024-02-17 ncurses 6.4 Library calls</H1>
<PRE>
-<!-- Manpage converted by man2html 3.0.1 -->
+<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>NAME</H2><PRE>
- <B>getch</B>, <B>wgetch</B>, <B>mvgetch</B>, <B>mvwgetch</B>, <B>ungetch</B>, <B>has_key</B> - get
- (or push back) characters from <B>curses</B> terminal keyboard
-</PRE>
-<H2>SYNOPSIS</H2><PRE>
- <B>#include</B> <B><curses.h></B>
- <B>int</B> <B>getch(void);</B>
- <B>int</B> <B>wgetch(WINDOW</B> <B>*win);</B>
- <B>int</B> <B>mvgetch(int</B> <B>y,</B> <B>int</B> <B>x);</B>
- <B>int</B> <B>mvwgetch(WINDOW</B> <B>*win,</B> <B>int</B> <B>y,</B> <B>int</B> <B>x);</B>
- <B>int</B> <B>ungetch(int</B> <B>ch);</B>
- <B>int</B> <B>has_key(int</B> <B>ch);</B>
+</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 <EM>curses</EM> terminal keyboard
-</PRE>
-<H2>DESCRIPTION</H2><PRE>
- The <B>getch</B>, <B>wgetch</B>, <B>mvgetch</B> and <B>mvwgetch</B>, routines read a
- character from the window. In no-delay mode, if no input
- is waiting, the value <B>ERR</B> is returned. In delay mode, the
- program waits until the system passes text through to the
- program. Depending on the setting of <B>cbreak</B>, this is
- after one character (cbreak mode), or after the first new-
- line (nocbreak mode). In half-delay mode, the program
- waits until a character is typed or the specified timeout
- has been reached.
-
- Unless <B>noecho</B> has been set, then the character will also
- be echoed into the designated window according to the fol-
- lowing rules: If the character is the current erase char-
- acter, left arrow, or backspace, the cursor is moved one
- space to the left and that screen position is erased as if
- <B>delch</B> had been called. If the character value is any
- other <B>KEY_</B> define, the user is alerted with a <B>beep</B> call.
- Otherwise the character is simply output to the screen.
-
- If the window is not a pad, and it has been moved or modi-
- fied since the last call to <B>wrefresh</B>, <B>wrefresh</B> will be
- called before another character is read.
-
- If <B>keypad</B> is <B>TRUE</B>, and a function key is pressed, the
- token for that function key is returned instead of the raw
- characters. Possible function keys are defined in
- <B><curses.h></B> as macros with values outside the range of
- 8-bit characters whose names begin with <B>KEY_.</B> 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 received (which, on modern terminals, means an
- escape character), <B>curses</B> 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.
-
- The <B>ungetch</B> routine places <I>ch</I> back onto the input queue to
- be returned by the next call to <B>wgetch</B>. Note that there
- is, in effect, just one input queue for all windows.
-
-
- <B>Function</B> <B>Keys</B>
- The following function keys, defined in <B><curses.h></B>, might
- be returned by <B>getch</B> if <B>keypad</B> has been enabled. Note
- that not all of these are necessarily supported on any
- particular terminal.
-
- <I>Name</I> <I>Key</I> <I>name</I>
-
- 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(<I>n</I>) For 0 <= <I>n</I> <= 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 read
- 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 input 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_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
+</PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
+ <STRONG>#include</STRONG> <STRONG><curses.h></STRONG>
+
+ <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>
+
+ <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>
+ 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
+ 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
+ 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
+ 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.
+
+ <STRONG>o</STRONG> Otherwise the character is simply output to the screen.
+
+ If the window is not a pad, and it has been moved or modified since the
+ last call to <STRONG>wrefresh</STRONG>, <STRONG>wrefresh</STRONG> will be called before another character
+ is read.
+
+
+</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
+ begin with <STRONG>KEY_</STRONG>.
+
+ <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
+ 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 <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
+ notimeout mode after pressing the escape key until another key is
+ pressed.
+
+
+</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
+ windows.
+
+
+</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
+ 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:
- +-----+------+-------+
- | <B>A1</B> | <B>up</B> | <B>A3</B> |
- +-----+------+-------+
- |<B>left</B> | <B>B2</B> | <B>right</B> |
- +-----+------+-------+
- | <B>C1</B> | <B>down</B> | <B>C3</B> |
- +-----+------+-------+
- The <B>has_key</B> routine takes a key value from the above list,
- and returns TRUE or FALSE according as the current termi-
- nal type recognizes a key with that value.
+ +-----+------+-------+
+ | <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
+ (see <STRONG><A HREF="curs_initscr.3x.html">initscr(3x)</A></STRONG> and <STRONG><A HREF="resizeterm.3x.html">resizeterm(3x)</A></STRONG>). This code is returned
+ 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,
+ because (e.g., with <STRONG>xterm(1)</STRONG> mouse prototocol) <EM>ncurses</EM> must read
+ escape sequences, just like a function key.
-</PRE>
-<H2>RETURN VALUE</H2><PRE>
- All routines return the integer <B>ERR</B> upon failure and an
- integer value other than <B>ERR</B> (<B>OK</B> in the case of ungetch())
- upon successful completion.
+</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.
-</PRE>
-<H2>NOTES</H2><PRE>
- Use of the escape key by a programmer for a single charac-
- ter function is discouraged, as it will cause a delay of
- up to one second while the keypad code looks for a follow-
- ing function-key sequence.
-
- When using <B>getch</B>, <B>wgetch</B>, <B>mvgetch</B>, or <B>mvwgetch</B>, nocbreak
- mode (<B>nocbreak</B>) and echo mode (<B>echo</B>) should not be used at
- the same time. Depending on the state of the tty driver
- when each character is typed, the program may produce
- undesirable results.
-
- Note that <B>getch</B>, <B>mvgetch</B>, and <B>mvwgetch</B> may be macros.
-
- 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 <B>KEY_UP</B>,
- <B>KEY_DOWN</B>, <B>KEY_LEFT</B>, <B>KEY_RIGHT</B>, <B>KEY_HOME</B>, <B>KEY_END</B>,
- <B>KEY_NPAGE</B>, <B>KEY_PPAGE</B>, and function keys 1 through 12. The
- Ins key is usually mapped to <B>KEY_IC</B>.
+ The library also supports these extensions:
+ <STRONG>define_key</STRONG>
+ defines a key-code for a given string (see <STRONG><A HREF="define_key.3x.html">define_key(3x)</A></STRONG>).
-</PRE>
-<H2>PORTABILITY</H2><PRE>
- The *get* functions are described in the XSI Curses stan-
- dard, Issue 4. They read single-byte characters only.
- The standard specifies that they return <B>ERR</B> on failure,
- but specifies no error conditions.
-
- The echo behavior of these functions on input of <B>KEY_</B> or
- backspace characters was not specified in the SVr4 docu-
- mentation. This description is adopted from the XSI
- Curses standard.
-
- The behavior of <B>getch</B> and friends in the presence of han-
- dled 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
- <B><A HREF="read.2.html">read(2)</A></B> call in progress or not, and also (in some imple-
- mentations) depending on whether an input timeout or non-
- blocking mode hsd been set.
-
- Programmers concerned about portability should be prepared
- for either of two cases: (a) signal receipt does not
- interrupt <B>getch</B>; (b) signal receipt interrupts <B>getch</B> and
- causes it to return ERR with <B>errno</B> set to <B>EINTR</B>. Under
- the <B>ncurses</B> implementation, handled signals never inter-
- rupt <B>getch</B>.
-
- The <B>has_key</B> function is unique to <B>ncurses</B>. We recommend
- that any code using it be conditionalized on the
- <B>NCURSES_VERSION</B> feature macro.
+ <STRONG>key_defined</STRONG>
+ checks if there is a key-code defined for a given string (see
+ <STRONG><A HREF="key_defined.3x.html">key_defined(3x)</A></STRONG>).
-</PRE>
-<H2>SEE ALSO</H2><PRE>
- <B><A HREF="ncurses.3x.html">curses(3x)</A></B>, <B><A HREF="curs_inopts.3x.html">curs_inopts(3x)</A></B>, <B><A HREF="curs_mouse.3x.html">curs_mouse(3x)</A></B>,
- <B><A HREF="curs_move.3x.html">curs_move(3x)</A></B>, <B><A HREF="curs_refresh.3x.html">curs_refresh(3x)</A></B>. <B><A HREF="resizeterm.3x.html">resizeterm(3x)</A></B>.
+</PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
+ All routines return the integer <STRONG>ERR</STRONG> upon failure and an integer value
+ other than <STRONG>ERR</STRONG> (<STRONG>OK</STRONG> in the case of <STRONG>ungetch</STRONG>) upon successful completion.
+
+ <STRONG>ungetch</STRONG>
+ returns <STRONG>ERR</STRONG> if there is no more room in the FIFO.
+
+ <STRONG>wgetch</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
+
+ <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
+ keypad code looks for a following function-key sequence.
+ 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:
+ <STRONG>o</STRONG> the terminal description lists the most useful keys,
+ <STRONG>o</STRONG> the <EM>Enter</EM> key on the regular keyboard is already handled by the
+ standard ASCII characters for carriage-return and line-feed,
+ <STRONG>o</STRONG> depending on whether <STRONG>nl</STRONG> or <STRONG>nonl</STRONG> was called, pressing "Enter" on the
+ regular keyboard may return either a carriage-return or line-feed,
+ and finally
+ <STRONG>o</STRONG> "Enter or send" is the standard description for this key.
+ When using <STRONG>getch</STRONG>, <STRONG>wgetch</STRONG>, <STRONG>mvgetch</STRONG>, or <STRONG>mvwgetch</STRONG>, nocbreak mode
+ (<STRONG>nocbreak</STRONG>) and echo mode (<STRONG>echo</STRONG>) should not be used at the same time.
+ Depending on the state of the tty driver when each character is typed,
+ the program may produce undesirable results.
+ 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
+ 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>
+ 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 <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><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
+ described in <STRONG><A HREF="curs_get_wch.3x.html">curs_get_wch(3x)</A></STRONG>.
+ncurses 6.4 2024-02-17 <STRONG><A HREF="curs_getch.3x.html">curs_getch(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-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>
+</div>
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