9.33.1 Posix termios interface

These procedures are available when the feature identifier gauche.os.windows is not defined. See cond-expand in Feature conditional for how to switch code using feature identifiers.

Builtin Class: <sys-termios> ¶

{gauche.termios} POSIX termios(7) structure.

Instance Variable of <sys-termios>: iflag ¶

Instance Variable of <sys-termios>: oflag ¶

Instance Variable of <sys-termios>: cflag ¶

Instance Variable of <sys-termios>: lflag ¶

Instance Variable of <sys-termios>: cc ¶

The slots iflag, oflag, cflag and lflag contains non-negative integers representing bitmasks.

The slot cc contains a copy of c_cc array of struct termios, as an u8vector (see Uniform vectors for the details about u8vector). Since cc slot is a copy of the internal structure, you have to set! an u8vector to the slot explicitly to make changes to the c_cc array.

Throughout this section, argument port-or-fd refers to either a port object or a small integer representing system’s file descriptor. If port is not associated to the system terminal, an error is signaled. (You can check if port has an associated terminal by sys-isatty?. see Other file operations).

Function: sys-tcgetattr port-or-fd ¶

{gauche.termios} Returns terminal parameters in a <sys-termios> object, associated to port-or-fd.

Function: sys-tcsetattr port-or-fd when termios ¶

{gauche.termios} Sets terminal parameters associated to port-or-fd by termios, which must be an instance of <sys-termios>.

An integer argument when specifies when the changes take effect. Three variables are pre-defined for the argument:

TCSANOW ¶

The change is reflected immediately.

TCSADRAIN ¶

The change is reflected after all pending output is flushed.

TCSAFLUSH ¶

The change is reflected after all pending output is flushed, and all pending input is discarded.

Function: sys-tcsendbreak port-or-fd duration ¶

{gauche.termios} Transmits a zero stream for the specified duration to the terminal associated to port-or-fd. The unit of duration depends on the system; see man tcsendbreak(3) of your system for details.

Function: sys-tcdrain port-or-fd ¶

{gauche.termios} Waits until all output written to port-or-fd is transmitted.

Function: sys-tcflush port-or-fd queue ¶

{gauche.termios} Discards data in the buffer of port-or-fd, specified by queue, which may be one of the following values.

TCIFLUSH ¶

Discards data received but not read.

TCOFLUSH ¶

Discards data written but not transmitted.

TCIOFLUSH ¶

Do both TCIFLUSH and TCOFLUSH action.

Function: sys-tcflow port-or-fd action ¶

{gauche.termios} Controls data flow of port-or-fd by action, which may be one of the following values:

TCOOFF ¶

Suspends output transmission.

TCOON ¶

Restarts output transmission.

TCIOFF ¶

Transmits a STOP character to make the terminal device stop transmitting data to the system.

TCION ¶

Transmits a START character to make the terminal device resume transmitting data to the system.

Function: sys-tcgetpgrp port-or-fd ¶

{gauche.termios} Returns process group ID of the terminal associated to port-or-fd.

Function: sys-tcsetpgrp port-or-fd pgrp ¶

{gauche.termios} Sets process group ID of the terminal associated to port-or-fd to pgrp.

Function: sys-cfgetispeed termios ¶

Function: sys-cfsetispeed termios speed ¶

Function: sys-cfgetospeed termios ¶

Function: sys-cfsetospeed termios speed ¶

{gauche.termios} Gets/sets input/output speed (baud rate) parameter stored in termios object. Speed is represented by the following predefined numbers: B0, B50, B75, B110, B134, B150, B200, B300, B600, B1200, B1800, B2400, B4800, B9600, B19200, B38400.

Some system may support higher baud rate, such as B57600, B115200 or B230400. You can use symbol-bound? to check these options are defined. B0 is used to terminate the connection.

Function: sys-openpty :optional term ¶

{gauche.termios} Opens a pair of pseudo ttys, one for master and the other for slave, then returns two integers which are their file descriptors. An optional argument term must be, if passed, a <sys-termios> object; it sets the slave pty’s parameters.

You can use open-input-fd-port and/or open-output-fd-port to create a port around the returned file descriptor (see File ports). To obtain pseudo tty’s name, use sys-ttyname (see Other file operations).

This function is available only if the system supports openpty(3).

Function: sys-forkpty :optional term ¶

{gauche.termios} Opens a pair of pseudo ttys, one for master and the other for slave, sets the slave pty suitable for login terminal, then fork(2).

Returns two integers; the first value is a child pid for the parent process, and 0 for the child process. The second value is a file descriptor of the master pty.

An optional argument term must be, if passed, a <sys-termios> object; it sets the slave pty’s parameters.

This function is available only if the system supports forkpty(3).

Note: sys-forkpty has the same MT hazard as sys-fork (see Process management, for details). If you’re running multiple threads, use sys-forkpty-and-exec below.

Function: sys-forkpty-and-exec command args :key iomap term sigmask ¶

{gauche.termios} Does sys-forkpty, and lets the child process immediately execs the specified command with arguments args. This function doesn’t have the hazard in multi-thread environment.

The meanings of arguments command, args, iomap and sigmask are the same as sys-exec (see Process management). If the keyword argument term is given, it is used to initialize the slave pty.

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9.33.2 Common high-level terminal control

Function: without-echoing iport proc ¶

{gauche.termios} If iport is an input port connected to a terminal, sets the terminal mode non-echoing and call proc with iport as an argument. Before returning from without-echoing, or throwing an error, the terminal mode is reset to the original state when this procedure is called. The procedure returns whatever value(s) proc returns.

You can also pass #f to iport. In that case, this procedure tries to open a console (/dev/tty on Unix, CON on Windows) and set the console mode, then calls proc with the opened input port. An error is thrown if the procedure can not open a console.

If iport is other than above, this procedure simply calls proc with iport. This allows the caller to read password from redirected input, for example.

Note: Because of an implementation issue, on Windows native platforms this procedure always changes console mode of the standard input handle when iport is either #f or a terminal input port.

Function: has-windows-console? ¶

{gauche.termios} Returns #t iff the running Gauche is Windows-native and the process has attached console. On Unix platforms this procedure always returns #f.

The reason that cond-expand isn’t enough is that on Windows the program may start without console, but you can attach console afterwards. See Windows console API, for the details.