How to tell if a process exists

[Darryl Wagoner]

In article <26B867F8.38BB at wilbur.coyote.trw.com> rudoff at mdi.com writes:
>
>In a C program, how do you tell if a certain process exists? A
>kill(0,pid) works only if you own the process (or you're root). It
>seems like such a simple thing to request that it should be part of
>the standard C libraries for unix, but I can't seem to find the right
>thing to use.

No, you can use kill(0,pid) even if you don't own the process.  If the
process is running and own by someone else,  then you get a EPERM error,
if the process doesn't exist then you get ESRCH error, and if the
process is killable by you then kill returns a zero.  The error codes
may be different on Ultrix but you get the idea.


-- 
Darryl Wagoner		darryl at lemuria.MV.COM or uunet!virgin!lemuria!darryl
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