LXR busybox/console-tools/deallocvt.c

   1/* vi: set sw=4 ts=4: */
   2/*
   3 * Disallocate virtual terminal(s)
   4 *
   5 * Copyright (C) 2003 by Tito Ragusa <farmatito@tiscali.it>
   6 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
   7 *
   8 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
   9 */
  10
  11/* no options, no getopt */
  12
  13#include "libbb.h"
  14
  15/* From <linux/vt.h> */
  16enum { VT_DISALLOCATE = 0x5608 }; /* free memory associated to vt */
  17
  18int deallocvt_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  19int deallocvt_main(int argc UNUSED_PARAM, char **argv)
  20{
  21        /* num = 0 deallocate all unused consoles */
  22        int num = 0;
  23
  24        if (argv[1]) {
  25                if (argv[2])
  26                        bb_show_usage();
  27                num = xatou_range(argv[1], 1, 63);
  28        }
  29
  30        /* double cast suppresses "cast to ptr from int of different size" */
  31        xioctl(get_console_fd_or_die(), VT_DISALLOCATE, (void *)(ptrdiff_t)num);
  32        return EXIT_SUCCESS;
  33}
  34