in reply to Re: Detect Process End
in thread Detect Process End

Please excuse my ignorance, I am really a beginner at this. I don't really want any output at all. I don't want any information back from ps. I just want to get a "true" if the process is still running. TNX if you can get me over this hump.

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Re^3: Detect Process End
by NetWallah (Canon) on Nov 27, 2004 at 05:30 UTC
    Here is a simpler explanation of ikegami(++)'s post:

    What you are trying to do is to keep running "ps -p $a" until you get a null output.

    In order to do that, you need to look at the output of that command.

    The "system" command does NOT provide the output.

    The backticks ($info = `/bin/ps -p $a`) DO provide that, capturing the output into $info.

    You then need to look for a null $info.

        ...each is assigned his own private delusion but he cannot see the baggage on his own back.

      It's a bit hacky - but I've done it myself ;) THe only other trick is you need to use `ps -h -p $a` to omit the ps header (which would otherwise mean you never get a null string).