Question

I have this command launched in a bash script:

rsync -av $sourcedir/ $destdir/

how do I store the PID for that specific command in a variable in the same script?

i tried with:

rsync -av --stats $sourcedir/ $destdir/ && pid=$(echo $$)

but the pid reported for that operation in the log file differs from the one printed out echoing $pid

thanks for any help!

Answer 1

rsync -av --stats $sourcedir/ $destdir/ & pid=$!

Note & usage here. You run commands in parallel.

If you make rsync && pid=$!, it is wrong, because the command (rsync) is already finished at the point where you make the assignment (pid=$!), so it is make no sense to save its pid in a variable for obvious reasons.