Re: Async IO

Matthias Urlichs (smurf@work.smurf.noris.de)
3 Feb 1997 16:29:36 +0100

In linux.dev.kernel, article <199702030606.BAA00518@wolverine.hq.cic.net>,
Jared Mauch <jared@wolverine.hq.cic.net> writes:
> Signal 0 checks to see if the process exists.
>
> If it does, it returns success, if it doesn't, it returns
> error.
>
Wrong.

If the process doesn't exist, it returns -1, errno == ESRCH.

If you aren't allowed to kill the process, you get EPERM.

If you are, you get zero.

-- 
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were at one time new; and what we today hold up by example, will rank
hereafter as precedent.
                                -- Tacitus

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