PID of compound shell command

Question

In your shell (bash in my case), you can get the pid of the last backgrounded process with the $! variable:

command &
echo $!

However, I'm interested in a compound command:

commandA | commandB &
echo $!

In this case, the value of $! seems to be the PID of commandB. What I'm looking for is the PID of commandA. Is there an easy way to get it?

score 2 · Answer 1 · answered Dec 13 '10 at 02:07

2

jobs -l will list the PIDs of each member of the pipeline.

answered Dec 13 '10 at 02:07

Dennis Williamson

score 1 · Accepted Answer · edited May 23 '17 at 12:18

1

You should find what you need there.

edited May 23 '17 at 12:18

Community

answered Dec 13 '10 at 00:55

MatthieuP

I did find some good ideas there, thought ultimately I just went with a "ps | grep | awk" solution for pulling the pid of the first process in the chain. – Brian Ferris Dec 13 '10 at 02:33

2 Answers2