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From: gwyn@smoke.BRL.MIL (Doug Gwyn)
Newsgroups: comp.unix.questions
Subject: Re: Finding if a process is active
Message-ID: <13095@smoke.BRL.MIL>
Date: 13 Jun 90 04:19:26 GMT
References: <1629@s3.ireq.hydro.qc.ca>
Distribution: comp.unix.questions
Organization: U.S. Army Ballistic Research Laboratory, APG, MD.
Lines: 16

In article <1629@s3.ireq.hydro.qc.ca> godin@ireq.hydro.qc.ca (Andre Godin 8926) writes:
>   I have a process (written in C) running under SunOS 4.0.3 that
>have to find out if a process exist, knowing only his name.

Processes don't have names, only numbers (PIDs).  The image that was
exec()ed came from a file that had a name, but the process could
easily alter the only record of the name assigned to its argv[0],
which is normally set to the "simple part" of the file name by the
shell used to exec() the process.  (But that is just a convention,
not necessarily followed by all exec()ers.)

>   Is there a system call (or something else) that can tell me if
>a certain process is active?

kill(pid,0) will tell you whether or not process #pid is active,
assuming you have appropriate permissions.