shell script and child pid's

[DanKarron at UCBVAX.BERKELEY.EDU]

How can I catch the pid of a spawned process from sh ?

karron:~:181sh
# echo xxx &
xxx

# run in foreground, pid is not reported.

6649
# echo xxx > /dev/null &
6650
# run in background, pid is reported.

# xxx=`echo xxx > /dev/null &`
6652

# how do you get thd pid string into a shell variable ?

I know that you can run ps and recover the child pid from the parent pid,
but if the shell is telling you the pid, why not pick it up and use it ?
ps won't be able to tell you which child pid is the one you want if you
spawn a number is like-named children.

There must be a simple trick out there !
Cheers!

dan.

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