Re: How to lock an optical drive tray closed?

[Rene Herman <rene.herman@xxxxxxxxxxxx>]

On 07-11-07 09:19, Steve R. Hastings wrote:

> Hello.  I'm trying to figure out how to lock the tray of an optical
> drive, so that the drive will not open the tray when the user presses
> the hardware "eject" button on the drive.
>
> This seems straightforward, because there is a well-documented list of
> IOCTLs for optical drive control, and one of them is CDROM_LOCKDOOR.
> (See Edward A. Falk's "cdrom.txt" doc file, and
> also /usr/include/linux/cdrom.h.)
>
> However, in my tests, the drive still ejects the disk even when I use
> the CDROM_LOCKDOOR IOCTL to lock it.

Works for me on a pata/sr driven CD-ROM and DVD. The description sort of 
makes it sound like the ioctl is a toggle, so are you perhaps not passing 
the 1/0 lock/unlock argument?

Rene.

/* gcc - W -Wall -o lock lock.c */

#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <fcntl.h>
#include <unistd.h>

#include <linux/cdrom.h>

int main(int argc, char *argv[])
{
	int i, lock = 1;

	while ((i = getopt(argc, argv, "u")) != -1) {
	       if (i != 'u')
		       goto usage;
	       lock = 0;
	}
	if (optind >= argc) {
usage:		
		fprintf(stderr, "usage: %s [-u] <device>\n", argv[0]);
		return EXIT_FAILURE;
	}

	i = open(argv[optind], O_RDONLY);
	if (i < 0) {
		perror("open");
		return EXIT_FAILURE;
	}
	if (ioctl(i, CDROM_LOCKDOOR, lock) < 0) {
		perror("ioctl");
		return EXIT_FAILURE;
	}
	if (close(i) < 0) {
		perror("close");
		return EXIT_FAILURE;
	}
	return EXIT_SUCCESS;
}