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Full Discussion: will child processes be created when executing "ps"?
Top Forums Shell Programming and Scripting will child processes be created when executing "ps"? Post 302506741 by Chubler_XL on Monday 21st of March 2011 08:52:19 PM
Old 03-21-2011
Probably better off using a lockfile with the process ID in it.

Code:
LOCK=/var/run/myscript.pid
# Test if lock file already exists and
# Send process NULL signal to test if it's running
# if so exit - cause job is already running
[ -e $LOCK ] && kill -0 `cat $LOCK` 2> /dev/null && exit 2
 
# Cleanup lockfile on exit, interrupt, quit or terminate
trap "{ rm -f $LOCK ; exit ; }" 0 2 3 15
echo $$ > $LOCK
 
# Rest of your script here

Last edited by Chubler_XL; 03-21-2011 at 10:10 PM..
This User Gave Thanks to Chubler_XL For This Post:
rbatte1
 

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