Using grep to remove line and write back to same file!?
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Using grep to remove line and write back to same file!?
I search the forum and get some help to remove a line starting with specific word with grep. Here is what I found
grep -v '^cc$' data.txt
Here I remove all lines with on 'cc' in that line. But I want the result write back to data.txt
I try several ways
grep -v '^cc$' data.txt > output.txt # works but to another file
echo `grep -v '^cc$' data.txt` > data.txt # didn't work, all carets gone, become one line
grep -v '^cc$' data.txt > data.txt # data.txt is empty after running this
How can I save the result of grep to the input file?
Grep has some interesting options and is a good tool, but generally I wouldn't consider that a job for grep... That's a job for sed or awk (or perl even).
I don't want to create a intermediate file but sed works perfectly for my case. Thanks a lot.
Quote:
Originally Posted by rweaver
Grep has some interesting options and is a good tool, but generally I wouldn't consider that a job for grep... That's a job for sed or awk (or perl even).
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