in reply to Keep a "system" process running if script is prematurely exited?

Under bash, you can use the disown command to detach it from the process and make it owned by the top-level process init. From bash: 
# gedit &
# disown $!

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Where $! is the last process id. To do this in Perl, I tried this: 
# perl -e 'system q{gedit &}'

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It starts gedit in its own window on my Ubuntu system and returns to the shell prompt. Then I close the terminal, and voila! gedit is still running. Can anyone tell us why disown is not needed in this case?

HTH,
SSF

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Re^2: Keep a "system" process running if script is prematurely exited?
by cdarke (Prior) on Jun 17, 2010 at 07:54 UTC
    Probably because bash shell option huponexit is set to off (see shopt for option settings).
    By the way, disown -h will supress HUP for a specific job, see help disown
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Re^2: Keep a "system" process running if script is prematurely exited?
by Anonymous Monk on Jun 17, 2010 at 06:32 UTC
    Probably because the perl process that launched gedit is finished (isn't connected to the shell anymore ie STDIN/STDOUT/STDERR are closed)

    You can confirm by comparing strace/truss output with 

    perl -e 'system q{gedit &} scalar <>;'

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