Shell script runs two functions as child processes (via &).
Both of them went to sleep (via sleep command).

Is it possible to wake them?

I have their pids.


I don't want to run sleep with & and wait


A rather barbaric way to do this would be to kill the sleep process (not the whole subshell in which your script/function runs). Consider the following shell script:

sleep 20
echo "Done!"

or, with a function:


function gotosleep()
    sleep 20
    echo "Done!"

gotosleep &
sleep 60 # Not really necessary, keeps the script in foreground.

Then, find the sleep process:

$ ps -ef | grep sleep
you    PID    PGID  ... sleep 20

And kill it:

$ kill PID

You script will then output (at least in bash):

./script.sh: line 2: PID Terminated    sleep 20

Since you don't want to wait properly, you'll have to do with Bash's little message. If you change your mind, have a look at this question:

sleep 20 &
if wait $! 2>/dev/null; then
    # Keep working
    echo "Done!"
    return # from function
  • I don't like the idead of sleeping in a new subprocees ( at least not explicitly) – yuris May 8 '16 at 14:42
  • @yuris That's not what I'm doing here. I believe my sleep process runs in the same "shell" the function does (if you use a function). The only time I used & was to send the function to background, which is exactly what you did. – John WH Smith May 8 '16 at 14:44
  • I see, the issue will be greping the correct pid... – yuris May 8 '16 at 14:49

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