Re: How to capture pid

From: Harry Putnam (reader_at_newsguy.com)
Date: 03/03/04 

To: beginners@perl.org
Date: Wed, 03 Mar 2004 10:36:06 -0600

zentara <zentara@highstream.net> writes:

> On Tue, 02 Mar 2004 18:07:58 -0600, reader@newsguy.com (Harry Putnam)
> wrote:
>>
>>For some reason the pid printed does not match the output of ps:
>>
>>actual sample script"
>>
>>Note the script outputs 15173 and ps shows 30335
>>
>>Do you have an idea what is happening here?
>
> Yeah, you are getting the parent pid in the perl script.
> When you try to use system or exec to start another
> process, perl gets the pid of the very first part of the whole
> transaction, which is usually the pid of the xterm or the
> bash shell which will run your command with a second pid.
> It usually works ok, because when you kill the parent pid,
> it's children get killed too, so we hardly ever have to deal
> with them being different.

If you want to log it for SIGHUP in /var/run/process.pid would the
parent work as well?

> Use Proc::ProcessTable to get the pid of your program name.
> Here is an example:

---8<snip script

Not sure I understand what I'm supposed to be seeing.
None of this output resembles a pid.

I shortened the count up to 10 and watched it output to STDOUT and
to a separate tty... output

STDOUT
1
2
3
[...]

other TTY
1a
2a
3a
[...]'

NOt sure I get what this has to do with two pids involved.

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