
Chopping off the last field of each line?
I'm working on the Web site for Creating Cool Web Sites and just realized that the little Unix trick I used while editing a file is actually a beautiful example of why so many people love Unix so much, so I thought I'd share it. The problem: a file where lines have 1-10 words + a last field value (in this case, a page number) that I don't want. The challenge is to figure out how to easily remove that last field, when there are a variable number of fields on the line.
How does this work? The rev command reverses each line of input, so that means that the first field of each now-reversed line is the field that we want to remove. That's easily done with cut with the -f2- flag (that means output field two through the end of the line). Then, finally, we re-reverse (that is, fix) each line and save the output in a new file.$ rev inputfile | cut -f2- | rev > outputfile Quickly and easily done.
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Never miss another useful Q&A article again! Subscribe to AskDaveTaylor with Google Reader. well done Posted by: pedestrian at August 19, 2007 9:20 AMtry this awk '{$NF=""; print $0}' Cheers I have a lot to say, but ...
I do have a comment, now that you mention it!
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