You can only suspend a job that was started in your current shell. To suspend a running job, press <Ctrl>Z (or the current defined suspend key). The job will stop running, but will remain available (and can be continued).
$If <Ctrl>Z does not work, your suspend key may not be set up correctly. To identify the suspend key, use the following command:
sort bigfile.dat >bigfile.out <Ctrl>Z + Stopped sort bigfile.dat>bigfile.out
$This command line looks for the word
stty -a | grep suspswtch = ^@;susp = ^Z;start = ^Q;stop = ^S;
suspin the stty settings. If it is present, it will tell you the current suspend key. If it is not present, or if you want to change it to another key, you can modify it using the stty command. For example, to make <Ctrl>Q the suspend key, enter the following:
$(The ``^Q'' is entered by typing a caret (^) followed by a letter ``Q''.)
stty susp ^Q