Commands not working in crontab

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1

I have the following two lines in my crontab:

0 5 * * 1-5 DISPLAY=:0 amarok -p
45 6 * * 1-5 DISPLAY=:0 qdbus org.ktorrent.ktorrent /core org.ktorrent.core.setSuspended false > /dev/null

Both commands work when I enter them in the terminal (with the “DISPLAY=:0” part removed). None or the commands work from crontab. The first one (amarok) gives the following mailed to me:

unnamed app(9705): KUniqueApplication: Cannot find the D-Bus session server: "/bin/dbus-launch terminated abnormally with the following error: No protocol specified
Autolaunch error: X11 initialization failed.
"

unnamed app(9685): KUniqueApplication: Pipe closed unexpectedly.

The second one (ktorrent) gives this:

Could not connect to D-Bus server: org.freedesktop.DBus.Error.Spawn.ExecFailed: /bin/dbus-launch terminated abnormally with the following error: No protocol specified
Autolaunch error: X11 initialization failed.

2

On 2013-09-04 19:46, Per 68 wrote:
>
> I have the following two lines in my crontab:
>>
>> 0 5 * * 1-5 DISPLAY=:0 amarok -p
>> 45 6 * * 1-5 DISPLAY=:0 qdbus org.ktorrent.ktorrent /core
>> org.ktorrent.core.setSuspended false > /dev/null

That’s 3 lines.

Please, this is difficult to decipher, because lines have wrapped round.
Please use code tags for command outputs and listings - the ‘#’ in the
web editor. View this thread for instructions

Besides that, you can not call a GUI from cron.

–
Cheers / Saludos,

Carlos E. R.
(from 11.4, with Evergreen, x86_64 “Celadon” (Minas Tirith))

3

Those commands run in the background. It is not even sure that X is running. When X is running, It is not sure that a GUI user is loged in. And even if a GUI user is loged in and is using DISPLAY 0:0 processes may not be allowed to open windows on a display without consent of the owner of that display. Not even root is allowed to do that.

4

Sorry. Here’s the same using CODE tags:

0 5 * * 1-5 DISPLAY=:0 amarok -p
45 6 * * 1-5 DISPLAY=:0 qdbus org.ktorrent.ktorrent /core org.ktorrent.core.setSuspended false > /dev/null

I’ve googled “amarok cron” and found many questions similar to mine. The answer has been to add DISPLAY=:0 to the beginning of the command line and the person asking the question has said it worked in all threads I looked into. These has been gqustions mostly from Ubuntu users, but also from users of Arch and Gentoo. I know from personal experience that it worked on Mageia before I changed to openSUSE. It even worked for me for 2 days a couple of weeks back in openSUSE. It then stopped working without me editing the crontab. Both Amarok and Ktorrent is already running when these commands are executed if that matters.

5

Hi
Cron by default knows no paths to files etc, have you tried exporting the DISPLAY variable first in your crontab and add the full path to amorak and qdbus;


export DISPLAY=":0"
0 5 * * 1-5 /usr/bin/amarok -p
45 6 * * 1-5 /usr/bin/qdbus org.ktorrent.ktorrent /core org.ktorrent.core.setSuspended false > /dev/null

Assuming both programs are in /usr/bin, you could also set the PATH statement in your crontab. I’m assuming this is for showing some status of those programs?

6

Adding the path to the commands did unfortunately not change anything.

7

I’ve solved the problem, or at least found a workaround. The line in crontab doesn’t work if I reboot my computer, but if I log out and log in again as the same user it starts working again.