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# 1  
Old 01-29-2009
trap
Hi

At the beginning of my script, i will create a file and at the end of the script i will delete that.

But i got to delete the file even if the process is forcefully killed, or server is rebooted...

I think i can make use of trap signal, but couldnt figure out how and where to use in my script.

What will be structure of the command?
# 2  
Old 01-29-2009
trap cannot "trap" all signals, for example SIGKILL is "immune" to a trap.

Near the top of your file:

Code:
#!/bin/ksh

trap "rm -f somefile; exit 1" INT  # you can add more signals here

will execute the command in quotes when CTRL/C -- SIGINT -- is sent to the process.
kill -l (that's the letter ELL) will show you the names of your signals. Be aware that not all signals need to be trapped nor can they be.
# 3  
Old 01-29-2009
If it's bash or ksh (maybe others too) you can use 'trap something 0', which will run on the virtual "EOF" signal.
# 4  
Old 01-29-2009
pludi is helpfully pointing out - you ought know that it is possible to make your trap statement do the cleanup on exit - in ksh anyway, I dunno about bash.
Code:
trap "rm -f somefile; exit " 0 INT QUIT SEGV BUS

# 5  
Old 01-29-2009
trap
Quote:
Originally Posted by jim mcnamara
trap cannot "trap" all signals, for example SIGKILL is "immune" to a trap.

Near the top of your file:

Code:
#!/bin/ksh

trap "rm -f somefile; exit 1" INT  # you can add more signals here

will execute the command in quotes when CTRL/C -- SIGINT -- is sent to the process.
kill -l (that's the letter ELL) will show you the names of your signals. Be aware that not all signals need to be trapped nor can they be.
Thankyou.
But what does 1 indicate. Is that the numeric form of signal.
Where can i find the other numeric forms of signals.
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