How to get PID in backgrounded /bin/sh while loop?

[Larry Wall]

In article <MONTNARO.90Mar20094531 at spyder.crd.ge.com> montanaro at crdgw1.ge.com (Skip Montanaro) writes:
: 
: Given the small shell script:
: 
:     #!/bin/sh
: 
:     ... do some stuff ...
: 
:     while true ; do
: 
: 	... do some loopy stuff ...
: 
:     done &
: 
: how do you discover the process id of the backgrounded while loop process?
: 
: A colleague suggested I write a small C program that just calls getppid(2),
: but that is overkill for the situation I have at hand. I've tried various
: combinations of quoting $$, evaling things containing it, and so on, but
: nothing yields helpful results. $! is undefined within the loop.

How 'bout

	pid=`perl -e 'print getppid;'`

Larry Wall
lwall at jpl-devvax.jpl.nasa.gov