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Old 01-13-2011, 09:31 PM   #1
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what is the meaning $$ in shell

Hi I saw this entry in a script

export TEMP_HOME=/temp/$$

when I do echo $$ on the command prompt I am getting a number, can some one tell me what this mean ($$)

Thanks & Best Regards
Old 01-13-2011, 09:57 PM   #2
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Old 01-13-2011, 09:58 PM   #3
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$$ expands to the process ID of the shell.

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Old 01-13-2011, 11:25 PM   #4
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thank you guys, I was wondering why it was changing, so it was giving the process id of the process great Thanks again


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