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When I do a kill -SIGUSR1 $PPID I get kill: (1) - Operation not permitted . How can I overcome this?

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up vote 2 down vote accepted

My parent process had died for some reason. This caused the issue. I took care of that and the problem got solved.

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You don't have permissions to send this signal. If you have sudo rights, do sudo kill -SIGUSR1 $PPID

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I don't think that is the case. I am able to send SIGUSR1 from a sub-shell and the default disposition is taken. – vpillai Feb 19 '13 at 3:32
if you do ps aux | grep $PPID you should see as which user that process is running. If you are not root, and this proc is running as another user than yourself, then you will most likely have no permissions to send signals to it. – mauro.stettler Feb 19 '13 at 3:41
could you please post the output of whoami and ps aux | grep $PPID? – mauro.stettler Feb 19 '13 at 3:42
vysakhp 18563 0.0 0.0 90820 1772 ? S 08:50 0:00 sshd: vysakhp@pts/1 -bash-3.2$ whoami vysakhp – vpillai Feb 19 '13 at 4:15

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