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weird behavior of grep -P

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# 1  
Old 12-20-2007
weird behavior of grep -P
I met a problem in using grep -P.

There is a text file, temp.txt, whose content is:
dddd
abc

I ran the command:

grep -P "\s*abc" temp.txt

The result I expected is:
abc

But, the actual result is:
dddd
abc

Could anyone tell me what is wrong?

Thanks.
# 2  
Old 12-20-2007
Quote:
Originally Posted by pankai
I met a problem in using grep -P.

There is a text file, temp.txt, whose content is:
dddd
abc

I ran the command:

grep -P "\s*abc" temp.txt

The result I expected is:
abc

But, the actual result is:
dddd
abc

Could anyone tell me what is wrong?

Thanks.
\s in perl includes \n so the pattern matches dddd\nabc

Depending on your requirements you could do a "^\s*abc" or "\w*abc"
# 3  
Old 12-20-2007
Quote:
Originally Posted by DeepakS
\s in perl includes \n so the pattern matches dddd\nabc

Depending on your requirements you could do a "^\s*abc" or "\w*abc"
Got it. Thanks.
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