From: Michael Satterwhite Date: 2009-05-07T08:55:02+09:00 Subject: Re: system call not working under cron Robert Klemme wrote: > On 06.05.2009 23:10, Michael Satterwhite wrote: >> >> Please accept that the "new_picture" variable has a good value pointing >> to a new background. There are traces in the program that write values >> to a trace file that I can examine after the fact. The fact that the >> trace file is updated also shows the script is running. >> >> Does anyone know why this command would work from a console, but not >> from a cron job? > > This is likely due to X11's handling of permissions. Your cron job > simply does not have access rights to the X session. I do not know the > details but the man page of "xhost" may be a good starting point. Error > message that you get might also be a good indication. I didn't even know about xhost before this. According to the documentation, the command "xhost" without arguments will list those who have authorization for the xserver. My user id was authorized already - still won't run from cron. I did learn something from this one, though. Thanks ---Michael -- Posted via http://www.ruby-forum.com/.