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sed q predicate doubt

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# 1  
Old 11-03-2011
sed q predicate doubt
Hi,

Could anyone please explain me what the following command does?
Code:
sed -ne "/\"$var\"/{=;q}" file

# 2  
Old 11-03-2011
It is trying to print the line number where the value of $var is present in the file.
Code:
sed -ne "/$var/{=;q}" file

Code:
[root@bt]-> cat infile
a
b
c
d
e
f
g
h
[root@bt]-> var=c
[root@bt]-> sed -ne "/$var/{=;q}" infile
3

-n Do not print anything
/$var/{} Search for value in $var, if found execute whatever is there inside {}
= Print the line number
q Quit, basically quit when you find the first occurrence

HTH
--ahamed
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