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<H1 class="no-header">curs_getch 3x</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>
<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
+ <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
</PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
</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 af-
- ter 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.
+ 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.
- 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:
+ 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:
- <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 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 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 is a carriage-return, and if <STRONG>nl</STRONG> is
- enabled, it is translated to a line-feed after echo-
- ing.
+ <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.
+ <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 modi-
- fied since the last call to <STRONG>wrefresh</STRONG>, <STRONG>wrefresh</STRONG> will be
- called before another character is read.
+ 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 to-
- ken 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 char-
- acters. Their names begin with <STRONG>KEY_</STRONG>.
-
- <STRONG>o</STRONG> Other (user-defined) function keys which may be de-
- fined 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 es-
- cape 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 es-
- cape 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 <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 pressed.
+ 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>.
+
+ <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
+ 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.
+
+ In <STRONG>ncurses</STRONG>, 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
+ 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.
+ 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.
</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 neces-
- sary 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 par-
- ticular terminal.
-
- <STRONG>o</STRONG> The naming convention may seem obscure, with some ap-
- parent 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.
-
- <EM>Name</EM> <EM>Key</EM> <EM>name</EM>
- -------------------------------------------------
- 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 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
+ <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.
+
+ <EM>Name</EM> <EM>Key</EM> <EM>name</EM>
+ -------------------------------------------------
+ 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 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
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> |
- +-----+------+-------+
- A few of these predefined values do <EM>not</EM> correspond to a
- real key:
+ +-----+------+-------+
+ | <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">curs_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_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="keypad.3x.html">keypad(3x)</A></STRONG> has been enabled, because (e.g., with <EM>xterm</EM>
- mouse prototocol) ncurses must read escape sequences,
- just like a function key.
+ <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 <EM>xterm</EM> mouse prototocol) ncurses 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 returns <STRONG>TRUE</STRONG> or <STRONG>FALSE</STRONG> according to whether the
- current terminal type recognizes a key with that value.
+ 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.
The library also supports these extensions:
<STRONG>define_key</STRONG>
- defines a key-code for a given string (see <STRONG>de-</STRONG>
- <STRONG><A HREF="define_key.3x.html">fine_key(3x)</A></STRONG>).
+ defines a key-code for a given string (see <STRONG><A HREF="define_key.3x.html">define_key(3x)</A></STRONG>).
<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>).
+ 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><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 ungetch())
- upon successful completion.
+ 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 ERR if there is no more room in the FIFO.
+ returns <STRONG>ERR</STRONG> if there is no more room in the FIFO.
<STRONG>wgetch</STRONG>
- returns ERR if the window pointer is null, or if
- its timeout expires without having any data, or if
- the execution was interrupted by a signal (<STRONG>errno</STRONG>
- will be set to <STRONG>EINTR</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>).
- Functions with a "mv" prefix first perform a cursor move-
- ment using <STRONG>wmove</STRONG>, and return an error if the position is
- outside the window, or if the window pointer is null.
+ 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 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.
-
- 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 accord-
- ing 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_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:
+ 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.
+
+ 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 han-
- dled by the standard ASCII characters for carriage-re-
- turn and line-feed,
+ <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> 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.
+ <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 un-
- desirable results.
+ 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>.
+ 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
+ <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-PORTABILITY">PORTABILITY</a></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 <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 docu-
- mentation. This description is adopted from the XSI Curs-
- es standard.
-
- The behavior of <STRONG>getch</STRONG> 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 im-
- plementation of handled signal receipt interrupts a
- <STRONG>read(2)</STRONG> call in progress or not, and also (in some imple-
- mentations) 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 re-
- lated terminfo capabilities, but no higher-level functions
- use the feature. The implementation in ncurses is an ex-
- tension.
-
- <STRONG>KEY_RESIZE</STRONG> is an extension first implemented for ncurses.
- NetBSD curses later added this extension.
-
- Programmers concerned about portability should be prepared
- for either of two cases: (a) signal receipt does not in-
- terrupt <STRONG>getch</STRONG>; (b) signal receipt interrupts <STRONG>getch</STRONG> and
- causes it to return ERR 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 using it be conditionalized on the <STRONG>NCURS-</STRONG>
- <STRONG>ES_VERSION</STRONG> feature macro.
+ 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
+ <STRONG>EINTR</STRONG>.
+
+ The <STRONG>has_key</STRONG> function is unique to <STRONG>ncurses</STRONG>. 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_outopts.3x.html">curs_outopts(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_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_outopts.3x.html">curs_outopts(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_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) li-
-
brary are described in <STRONG><A HREF="curs_get_wch.3x.html">curs_get_wch(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>.
- <STRONG><A HREF="curs_getch.3x.html">curs_getch(3x)</A></STRONG>
+
<STRONG><A HREF="curs_getch.3x.html">curs_getch(3x)</A></STRONG>
</PRE>
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