/*
* Program to control the console lock keys states
*
* Build with “gcc -o lockkeys lockkeys.c”
* cp lockkeys numlock.init.string /etc/
* in /etc/inittab
* “snum::sysinit:/etc/lockkeys numlock on </dev/console>;/dev/console 2>;&1”
*/
#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
#include <signal.h>
#include <sys/stat.h>
#include <linux/kd.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#define ERROR -1
int main( int argc, char *argv[] )
{
char c;
int function, key;
int fd; /* File descriptor for console (/dev/tty/) */
if ( argc != 3 ) {
fprintf( stderr, “Usage: lockkeys key on | off | togglen” );
exit( 1 );
}
if ( !strcmp( argv[2], “off” ))
function=0;
else if ( !strcmp( argv[2], “on” ))
function=1;
else if ( !strcmp( argv[2], “toggle” ))
function=2;
else {
fprintf( stderr,
“lockkeys: function must be on, off, or togglen” );
exit( 1 );
}
if ( !strcmp( argv[1], “numlock” ))
key= LED_NUM;
else if ( !strcmp( argv[1], “capslock” ))
key= LED_CAP;
else if ( !strcmp( argv[1], “scrolllock” ))
key= LED_SCR;
else {
fprintf( stderr,
“lockkeys: key must be numlock, capslock, or scrolllockn” );
exit( 1 );
}
/* To be used as the fd in ioctl(). */
if ((fd = open(“/dev/console”, O_NOCTTY)) == ERROR)
{
perror(“open”);
exit(ERROR);
}
if ( ioctl( fd, KDGETLED, &c ) != 0 ) {
perror( “lockkeys: can’t get current lock state” );
exit( 2 );
}
if ( function == 0 )
c &= ~key;
else if ( function == 1 )
c |= key;
else
c ^= key;
if ( ioctl( fd, KDSETLED, c ) != 0 ) {
perror( “lockkeys: error setting lock state” );
exit( 2 );
}
close(fd);
return 0;
}