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echo "$$date"

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# 1  
Old 05-11-2010
echo "$$date"
Hi
When giving this command, it prints 264date or echo $$ prints 264. What does this 264 mean?
# 2  
Old 05-11-2010
264 is the process id (of the shell you are currently in)

Code:
echo $$

# 3  
Old 05-11-2010
Quote:
Originally Posted by erora
Hi
When giving this command, it prints 264date or echo $$ prints 264. What does this 264 mean?
echo $$ gives you the pid of the process initiating the echo function or command.Smilie
# 4  
Old 05-11-2010
$$ is a special variable...it's your PID. So you're basically providing a session-specific string...
# 5  
Old 05-11-2010
Quote:
Originally Posted by pseudocoder
264 is the process id (of the shell you are currently in)

Code:
echo $$

Quote:
Originally Posted by Reboot
echo $$ gives you the pid of the process initiating the echo function or command.Smilie
That's not always true. The value of $$ in a subshell (and a sub-subshell, etc) is identical to the $$ value in its parent, eventhough a subshell can be a different process with a different pid.

Regards,
Alister
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