trap command

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# 1  
Old 08-18-2011
trap command

dear all;
I can't under stand what does "trap" command do:
for example see below:
trap "echo; echo no interrupts >&2; sleep 3" 2 3 15

Plz , can any body explain the action of this command?

# 2  
Old 08-18-2011
TRAP is looking for signals "2" "3" and "15" where

SIGHUP 1 Exit Hangup (see termio(7I))
SIGINT 2 Exit Interrupt (see termio(7I))
SIGTERM 15 Exit Terminated

*trap [ arg sig [ sig2...]]

If it sees any signals 2, 3 or 15 passed to your process, it will capture those and prevent them from being passed on to your process, instead it will display the echo message.
This User Gave Thanks to dude2cool For This Post:
# 3  
Old 08-18-2011
thanks man that was helpful Smilie
# 4  
Old 08-18-2011
Smilie, glad I was of some help. Have fun with trap Smilie.
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