KEYBOARD(2) KEYBOARD(2)
NAME
initkeyboard, ctlkeyboard, closekeyboard - keyboard control
SYNOPSIS
#include <u.h>
#include <libc.h>
#include <thread.h>
#include <keyboard.h>
Keyboardctl *initkeyboard(char *file)
int ctlkeyboard(Keyboardctl *kc, char *msg)
void closekeyboard(Keyboard *kc)
DESCRIPTION
These functions access and control a keyboard interface for
character-at-a-time I/O in a multi-threaded environment,
usually in combination with mouse(2). They use the message-
passing Channel interface in the threads library (see
thread(2)); programs that wish a more event-driven, single-
threaded approach should use event(2).
Initkeyboard opens a connection to the keyboard and returns
a Keyboardctl structure:
typedef struct Keyboardct Keyboardctl;
struct Keyboardctl
{
Channel *c; /* chan(Rune[20]) */
char *file;
int consfd; /* to cons file */
int ctlfd; /* to ctl file */
int pid; /* of slave proc */
};
The argument to initkeyboard is a file naming the device
file from which characters may be read, typically /dev/cons.
If file is nil, /dev/cons is assumed.
Once the Keyboardctl is set up a message containing a Rune
will be sent on the Channel Keyboardctl.c to report each
character read from the device.
Ctlkeyboard is used to set the state of the interface, typi-
cally to turn raw mode on and off (see cons(3)). It writes
the string msg to the control file associated with the
device, which is assumed to be the regular device file name
with the string ctl appended.
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KEYBOARD(2) KEYBOARD(2)
Closekeyboard closes the file descriptors associated with
the keyboard, kills the slave processes, and frees the
Keyboardctl structure.
SOURCE
/sys/src/libdraw
SEE ALSO
graphics(2), draw(2), event(2), thread(2).
BUGS
Because the interface delivers complete runes, there is no
way to report lesser actions such as shift keys or even
individual bytes.
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