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Top Forums Shell Programming and Scripting Double square brackets question Post 302359803 by King Nothing on Wednesday 7th of October 2009 11:47:10 AM
Old 10-07-2009
Double square brackets question

Hi,
I just came across an interesting shell script syntax like the one below:
Code:
[[ $mode =  "INTERACTIVE" ]] && (trap 'rm -rf ${WORK_DIR}/*.$$; echo "\n\nInterrupted !!\n\n"; exit 4' 1 2 3 15)

Can someone please explain the code snippet above?
The trap command bit is fine but [[ $mode = "INTERACTIVE" ]] && is the hazy part.
Generally we use an if before [[ ]], but it is not being used here!

I was also experimenting with the below code snippet and it seemed to work fine as long as I was not putting #! /usr/bin/ksh at the top of the script.
Code:
[[ `ps -ef | grep Hawkmoon | grep -v grep` ]]

Why is it that it is running sans #! /usr/bin/ksh only?
I am using Solaris 5.8 by the way.
Thanks in advance Smilie.

Last edited by King Nothing; 10-07-2009 at 01:16 PM..
 

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