How do I find out the process id of the backgrounded process?

Question

I've got a command (program) that I'd like to run with nohup and background it. Like

nohup command > logfile.txt &

How do I find out the process ID? I would like to be able to write the process id in a file, read it later and kill the process programatically.

score 7 · Accepted Answer · answered Jan 10 '11 at 20:18

7

In your script:

nohup command > logfile.txt &
echo $! > /var/run/command.pid

answered Jan 10 '11 at 20:18

leonbloy

score 3 · Answer 2 · answered Jan 10 '11 at 20:12

3

You can use $!. Referenced in the bash documentation.

answered Jan 10 '11 at 20:12

Phil Hollenback

score 2 · Answer 3 · answered Jan 10 '11 at 20:12

2

You can use ps and grep to find the process in the process list and then awk to parse the output and find the actual PID:

ps -ef | grep -v grep | grep YOUR_PROCESS_NAME | awk '{ print $2 }'

answered Jan 10 '11 at 20:12

Massimo

score 0 · Answer 4 · answered Jan 10 '11 at 20:10

0

You could try:

ps aux | grep -v grep | grep program name

That'll check the running processes, grep for the program name, but exclude the grep itself.

answered Jan 10 '11 at 20:10

Publiccert

This solution would not work because I run multiple instances of the same program (2 to be exact), and I need to differentiate between them. EDIT: I _think_ it wouldn't work... would it? :) – Jan 10 '11 at 22:33

4 Answers4