setconsole.c

linux下驱动编写实例。

/*
 * setconsole.c -- choose a console to receive kernel messages
 *
 * Tested with 2.0 2.2 2.4  on x86
 * Tested with 2.0          on SPARC
 * Tested with 2.0          on Alpha
 * Tested with     2.2      on ARM
 * Tested with     2.2      on PowerPC
 * Tested with     2.2      on SPARC64
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <sys/ioctl.h>

int main(int argc, char **argv)
{
    char bytes[2] = {11,0}; /* 11 is the TIOCLINUX cmd number */

    if (argc==2) bytes[1] = atoi(argv[1]); /* the chosen console */
    else {
        fprintf(stderr, "%s: need a single arg\n",argv[0]); exit(1);
    }
    if (ioctl(STDIN_FILENO, TIOCLINUX, bytes)<0) {    /* use stdin */
        fprintf(stderr,"%s: ioctl(stdin, TIOCLINUX): %s\n",
                argv[0], strerror(errno));
        exit(1);
    }
    exit(0);
}