Index for Section 3

Alphabetical listing for C

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curs_inopts(3)
NAME
  curs_inopts, cbreak, nocbreak, echo, noecho, halfdelay, intrflush, keypad,
  meta, nodelay, qiflush, noqiflush, raw, noraw, timeout, notimeut, wtimeout,
  typeahead - Curses routines that control terminal-input options

SYNOPSIS
  #include <curses.h>

  int cbreak(
	  void );

  int nocbreak(
	  void );

  int echo(
	  void );

  int noecho(
	  void );

  int halfdelay(
	  int tenths );

  int intrflush(
	  WINDOW *win,
	  bool bf );

  int keypad(
	  WINDOW *win,
	  bool bf );

  int meta(
	  WINDOW *win,
	  bool bf );

  int nodelay(
	  WINDOW *win,
	  bool bf );

  int raw(
	  void );

  int noraw(
	  void );

  void qiflush(
	  void );

  void noqiflush(
	  void );

  void timeout(
	  int delay );

  int notimeout(
	  WINDOW *win,
	  bool bf );

  void wtimeout(
	  WINDOW *win,
	  int delay );

  int typeahead(
	  int fd );

LIBRARY
  Curses Library (libcurses)

STANDARDS
  Interfaces documented on this reference page conform to industry standards
  as follows:

  cbreak, nocbreak, echo, noecho, halfdelay, intrflush, keypad, meta,
  nodelay, qiflush, noqiflush, raw, noraw, timeout, notimeout, wtimeout,
  typeahead:  XCURSES4.2

  Refer to the standards(5) reference page for more information about
  industry standards and associated tags.

DESCRIPTION
  The cbreak and nocbreak routines put the terminal into and out of cbreak
  mode, respectively.  In this mode, characters typed by the user are
  immediately available to the program, and erase/kill character-processing
  is not performed. When out of this mode, the tty driver buffers the typed
  characters until the user types a newline or carriage return. Interrupt and
  flow-control characters are unaffected by this mode. Initially, the
  terminal may or may not be in cbreak mode, as the mode is inherited;
  therefore, a program should call cbreak or nocbreak explicitly. Most
  interactive programs using Curses set the cbreak mode.

  Note that cbreak overrides raw.  (See curs_getch(3) for a discussion of how
  these routines interact with echo and noecho.)

  The echo and noecho routines control whether characters typed by the user
  are echoed by getch as they are typed. Echoing by the tty driver is always
  disabled, but initially getch is in echo mode, so characters are echoed as
  they are typed.  Authors of most interactive programs prefer to do their
  own echoing in a controlled area of the screen or not to echo at all, so
  they disable echoing by calling noecho. (See curs_getch(3) for a discussion
  of how these routines interact with cbreak and nocbreak.)

  The halfdelay routine sets half-delay mode, which is similar to cbreak mode
  in that characters typed by the user are immediately available to the
  program. However, after blocking for tenths tenths of seconds, halfdelay
  returns ERR if nothing has been typed.  The value of tenths must be a
  number between 1 and 255. Applications call the nocbreak routine to leave
  half-delay mode.

  If the intrflush routine enables or disables the intrflush option. When
  intrflush is enabled (bf is set to TRUE), all output in the tty driver
  queue is flushed when the user presses an interrupt key (interrupt, break,
  or quit). This flush operation gives the effect of faster response to the
  interrupt but causes Curses to have the wrong image of what is on the
  screen. Disabling the intrflush option (setting bf to FALSE) prevents
  output in the tty driver queue from being flushed. The default for the
  intrflush option is inherited from the tty driver settings.  The window
  argument is ignored.

  The keypad routine enables the keypad option associated with the user's
  terminal. If the keypad option is enabled (bf is set to TRUE), the user can
  press a function key (such as an arrow key) and wgetch returns a single
  value representing the function key, as in KEY_LEFT. If the keypad is
  disabled (bf is set to FALSE), Curses does not treat function keys
  specially, and the program has to interpret the escape sequences. If the
  keypad in the terminal can be turned on (made to transmit) and off (made to
  work locally), enabling the keypad option causes the terminal keypad to be
  turned on when wgetch is called. The default value for keypad is false.

  Initially, whether the terminal returns 7 or 8 significant bits on input
  depends on the control mode of the tty driver (see termios(4)). To force 8
  bits to be returned, applications call meta(win, TRUE). To force 7 bits to
  be returned, applications call meta(win, FALSE). The window argument, win,
  is always ignored. If the terminfo database capabilities smm (meta_on) and
  rmm (meta_off) are defined for the terminal, smm is sent to the terminal
  when meta(win, TRUE) is called and rmm is sent when meta(win, FALSE) is
  called.

  The nodelay routine enables and disables no delay mode. When this mode is
  enabled (bf is set to TRUE), the call causes getch to be a nonblocking
  call. In this case, if no input is ready, getch returns ERR. If no delay
  mode is disabled (bf is FALSE), getch waits until the user presses a key.

  While interpreting an input escape sequence, wgetch sets a timer while
  waiting for the next character. If the application calls notimeout(win,
  TRUE), then wgetch does not set a timeout interval. The purpose of the
  timeout is to differentiate between sequences received from a function key
  and those typed by a user.

  The raw and noraw routines place the terminal in and out of raw mode. Raw
  mode is similar to cbreak mode in that the typed characters are immediately
  passed through to the user program. The difference is that in raw mode, the
  interrupt, quit, suspend, and flow control characters do not generate a
  signal but are all passed through uninterpreted to the application. The
  behavior of the Break key depends on other bits in the tty driver that are
  not set by Curses.

  When applications use the noqiflush routine, Curses sets the NOFLSH
  condition in the tty driver to disable queue flushing. In this state, the
  normal flushing of input and output queues associated with the quit and
  interrupt characters is not done. (see termios(4)). When the application
  calls qiflush, Curses flushes the queues when the quit and interrupt
  characters are read.

  The timeout and wtimeout routines set blocking or nonblocking read for a
  given window. If delay is negative, blocking read is set; that is, the read
  operation waits indefinitely for input. If delay is zero, then nonblocking
  read is set; that is, the read operation returns ERR if no input is
  waiting. If delay is positive, then the read operation blocks for delay
  milliseconds, then returns ERR if there is still no input. Therefore, the
  timeout and wtimeout routines provide the same functionality as nodelay,
  plus (where delay is positive) the additional capability of being able to
  block for only a specified number of milliseconds.

  Curses performs "line-breakout optimization" by looking periodically for
  typeahead input while updating the screen. If input is found, and it is
  coming from a tty, Curses postpones the screen update until refresh or
  doupdate is called again. This optimization allows faster response to
  commands typed in advance. To do the typeahead checking, Curses normally
  uses the input FILE pointer passed to newterm, or stdin if initscr was
  called.  The typeahead routine tells Curses to check for typeahead input by
  using the specified file descriptor, fd. If fd is -1, then Curses performs
  no typeahead checking.

NOTES
  The header file <curses.h> automatically includes the header file
  <stdio.h>.

  Note that echo, noecho, and timeout may be macros.

RETURN VALUES
  All routines that return an integer return ERR upon failure and OK upon
  successful completion, unless otherwise noted in the preceding routine
  descriptions.

SEE ALSO
  Functions: curses(3), curs_getch(3), curs_initscr(3)

  Files: termios(4)

  Others: standards(5)

Index for Section 3

Alphabetical listing for C

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