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grep and store

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# 1  
Old 12-02-2005
grep and store
When i grep a file and store it in a file it is storing as a zero byte file any way to avoid that.....
# 2  
Old 12-02-2005
Post your command. There is no way to give an accurate answer without that. Here is a thought though. Are you doing something like:
Code:
grep "something" arunkumar.txt > arunkumar.txt

This will truncate the file first and then run the grep on that file; which will obviously output a zero byte file.
# 3  
Old 01-26-2006
Thank you but i want to do grep a same file and save in that file is that possible ?? please give some idea
# 4  
Old 01-26-2006
grep pattern filename >> filename

this would append the pattern search into the filename,

is that you want?
# 5  
Old 01-26-2006
Quote:
Originally Posted by arunkumar_mca
Thank you but i want to do grep a same file and save in that file is that possible ?? please give some idea
Not with grep. However you could do it with sed if you are on a gnu system.
# 6  
Old 01-26-2006
try this command

grep "expression" filename | & tee log

This work for all command , one output will redirected to standard output which is screen and another in the file name log.

rajesh
# 7  
Old 01-27-2006
Two solutions ...

With sed (2 steps):
Code:
sed -n '/expression/p' filename > tempfile
mv tempfile filename

With perl (1 step) :
Code:
perl -n -i -e 'print if /expression/' filename


Jean-Pierre.
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