sbin/comcontrol/comcontrol.c

/*-
 * Copyright (c) 1992 Christopher G. Demetriou
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote
 *    products derived from this software without specific written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/* comcontrol.c */

#include <sys/types.h>
#include <sys/ioctl.h>
#include <stdio.h>
#include <fcntl.h>


void usage(char *progname)
{
        fprintf(stderr, "usage: %s <filename> [[-]bidir]\n", progname);
        exit(1);
}

int main(int argc, char *argv[])
{
        int     fd;
        int     res;

        if ((argc < 2) || (argc > 3)) usage(argv[0]);

        fd = open(argv[1], O_RDONLY|O_NONBLOCK, 0);
        if (fd < 0) {
                fprintf(stderr, "%s: couldn't open file %s\n", argv[0], argv[1]);
                perror("open");
                exit(1);
        }

        if (argc == 2) {
                if (ioctl(fd, TIOCMGBIDIR, &res) < 0) {
                        perror("ioctl");
                        exit(1);
                }
                if (!res)  printf("-");
                printf("bidir\n");
        } else {
                if (!strcmp(argv[2],"bidir")) {
                        res = 1;
                } else if (!strcmp(argv[2],"-bidir")) {
                        res = 0;
                } else {
                        usage(argv[0]);
                }
                if (ioctl(fd, TIOCMSBIDIR, &res) < 0) {
                        perror("ioctl");
                        exit(1);
                }
        }

        close(fd);
}