set -m

-m
Job control is enabled (see Job Control). All processes run in a separate process group. When a background job completes, the shell 
prints a line containing its exit status.

set, unset, set -o, set -x, set -e, set +e, set -E, set +b, set -u, $?, exit, return, trap, PostgreSQL SET, set --erase (fish shell), set -gx