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.

In reply to Re^3: Detect Process End by NetWallah
in thread Detect Process End by rcolman

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