send signal to privileged application from unprivileged application

aral · 09-12-2006, 10:38 AM

I tried to send a signal from an application running as normal user to an application running as root and obviously the application running as root didn't get the signal (it had a signal handler for it ). What can I change in order for the root application to get the signal ? I sent the signal using kill(pid, signumber) and I used SIGUSR1 for sig number .. Can anyone help me ?

aral · 09-14-2006, 04:55 AM

does anyone know ?

aral · 09-20-2006, 07:55 AM

Please, I really need this !

aral · 09-22-2006, 09:48 AM

Is this really so difficult ? I've imagined I'm the only one who doesn't know such simple things ..

Matir · 09-22-2006, 10:00 AM

Have you read the kill(2) manpage?

Quote:

For a process to have permission to send a signal it must either be
privileged (under Linux: have the CAP_KILL capability), or the real or
effective user ID of the sending process must equal the real or saved
set-user-ID of the target process. In the case of SIGCONT it suffices
when the sending and receiving processes belong to the same session.

aral · 10-27-2006, 12:34 PM

So , what's the definition of "session" which the manual mentiones when it says : "when the sending and receiving processes belong to the same session " ?