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pattern matching question

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# 1  
Old 04-20-2011
pattern matching question
Hi Guys
I am trying to check if the pattern "# sign followed by one or several tabs till the end of the line" exists in my file. I am using the following query:
Code:
$ cat myfile | nawk '{if(/^#\t*$/) print "T"}'

Unfortunately it does not return the desired output since I know for sure that the line with the mention above pattern exists in the file.
May be someone can spot my error, thanks a lot
# 2  
Old 04-20-2011
try escaping the #

Code:
nawk '{if(/^\#\t*$/) print "T"}' myfile
or
nawk '{if(/^\#[ ][ ]*$/) print "T"}' myfile
or
$ perl -wle 'print "T" if /^\#\s+$/; ' myfile ## I prefer this.

# 3  
Old 04-20-2011
Simple, fast and stops at first.
Code:
if grep -q '^#\t*$'
then
 . . .
fi

Last edited by DGPickett; 04-20-2011 at 03:27 PM..
# 4  
Old 04-20-2011
Quote:
Originally Posted by aoussenko
I am trying to check if the pattern "# sign followed by one or several tabs till the end of the line" exists in my file.
Code:
awk '/^#\t+$/{print "T"}' file

# 5  
Old 04-20-2011
Thanks a lot.
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