How to check device user permissions?

[Evil-I]

Hi There,

I've been having an ongoing struggle trying to get a mythtv server up and running. The latest challenge is that although my tv tuners are being recognised at a low level with console based DVB apps, in myth TV its showing errors. Please see the full description at the MythTalk forum.

Now the chap who has responded to my cry for help on the myth tv forums has suggested it might either be a user permissions error for the device, or potentially other software using the devices and therefore locking the devices from myth-tv.

My DVB devices are basically:
/dev/dvb/adapter0/frontend0
/dev/dvb/adapter1/frontend0
/dev/dvb/adapter2/frontend0
/dev/dvb/adapter3/frontend0
/dev/dvb/adapter4/frontend0

with /dev/dvb/adapter0/frontend0 being my S2 satelite card and 1-4 being the two dual channel DVB-t tuners.

So the silly question is how do I check what the user permissions for a device are?

Also, how do I check that another programme is using the devices?

All help very much appreciated!

E-I

 

[BigglesPiP]

Maybe:

ls -lrath /dev/dev/*/*

Try running myth-tv as root (just as an experiment). If this works you just need to craft some udev rules.

 

[Evil-I]

Many thanks for the help!

ls -lrath /dev/dev/*/*
returns
crw-rw----+ 1 root video 212, 19 Sep 9 17:45 /dev/dvb/adapter4/frontend0

and running mythtv-setup as root, suddenly the devices are recognised correctly!

So, its definitely a device permissions issue, so how do I fix that?

Thanks in advance,

E-I

 

[BigglesPiP]

Put your user (the one who usually runs mythtv) in the "video" group.

 

[Evil-I]

Hi BigglesPiP,

Thanks for that, that fixed it!

Best,

M