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extract a certain number of lines from a file and dump them to another file

Terminal - extract a certain number of lines from a file and dump them to another file
grep '' -m X file1 > file2
2009-03-22 04:34:43
User: sardanapalos
Functions: grep
-4
Up
Down
extract a certain number of lines from a file and dump them to another file

It extracts X number of lines from file1 and dumps them to file2.Using grep with the empty string '' extracts the complete lines (i.e. no filtering takes place) and the -m flag indicates how many lines to extract out from the given file. Then using the redirect > operator we send the extracted lines to a new file.

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Alternatives

There is 1 alternative - vote for the best!

Terminal - Alternatives

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What others think

You could also use the head or tail command

head -X file1 > file2 tail -X file1 > file2

where X is the number of lines you want to extract from the top/bottom of file1.

Comment by gar 217 weeks and 2 days ago

awk ' NR = min { print } ' file1 > file2

Comment by maht 217 weeks and 2 days ago

where min and max (inclusive) are the line numbers you're interested in

Comment by maht 217 weeks and 2 days ago

ack my

Comment by maht 217 weeks and 2 days ago

ack my < and > got swallowed (twice !)

awk ' NR >= min && NR <= max { print } ' file1 > file2

fingers crossed

Comment by maht 217 weeks and 2 days ago

hmm this would be better because then it won't keep processing lines you don't want

NR < min { next } NR > max { exit } { print }

Comment by maht 217 weeks and 2 days ago

Your point of view

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