[mythtv] [PATCH] MythVideo & Mediamonitoring (suite)

[Leo Weppelman]

On Wed, Jun 16, 2004 at 03:06:07PM +0200, Xavier Hervy wrote:
> 
> Thx to try this patch :)

No thanks, just trying to build something I'd like to use ;-)

> I remove the close at the start of MythMediaDevice because when i made 
> my test, i made 3 observations :
> - I can mount a drive even if the device is open
> - I can't unmout drive if the device is open
> - i can't open device if the device is mounted.
> 
> see this thread for more information : 
> http://www.gossamer-threads.com/lists/mythtv/dev/71755
> Can you explicitly make the test which is describe in the post ?
> it's why i remove the close at the beginning, if i close it, 
> mediamonitor can't open the device to check the status.
> But i can make a mistake then i will try again and send feedback

I did. See the attached program and it's output... It looks like I can
either mount or open de cdrom device but not both... It's weird that
it works otherwise on your system. This is kernel 2.6.5-1-686, maybe
that makes a difference?


Leo.
-------------- next part --------------
#include <stdio.h>
#include <fcntl.h>
#include <linux/cdrom.h>

main()
{
        int fh, rc;
        rc = system("mount /cdrom");
        printf(" mount rc: %d\n", rc);

        if ((fh = open("/dev/cdrom",O_RDONLY | O_NONBLOCK | O_EXCL)) < 0) {
                perror("Open after mount:");
        }
        else {
                if (ioctl(fh,CDROM_LOCKDOOR,0) < 0) {
                        perror("CDROM_LOCKDOOR");
                }
                close(fh);
        }
        system("umount /cdrom");
        system("df");
        if ((fh = open("/dev/cdrom",O_RDONLY | O_NONBLOCK | O_EXCL)) < 0) {
                perror("Open before mount:");
        }
        rc = system("mount /cdrom");
        printf(" mount rc: %d\n", rc);
        if (fh >= 0) {
                if (ioctl(fh,CDROM_LOCKDOOR,0) < 0) {
                        perror("CDROM_LOCKDOOR");
                }
                close(fh);
        }
        system("umount /cdrom");
        system("df");
}

========== It's output ========
 mount rc: 0
Open after mount:: Device or resource busy
Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/vol1/var        103212320  45749892  52219548  47% /var
/dev/vol1/tmp           495844      8298    461946   2% /tmp
tmpfs                   254076         0    254076   0% /dev/shm
mount: /dev/cdrom already mounted or /cdrom busy
 mount rc: 8192
umount: /cdrom is not mounted (according to mtab)
Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/vol1/var        103212320  45749892  52219548  47% /var
/dev/vol1/tmp           495844      8298    461946   2% /tmp
tmpfs                   254076         0    254076   0% /dev/shm