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

grep '' -m X file1 > file2
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.

2009-03-22 04:34:43

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.
gar · 639 weeks and 1 day ago
awk ' NR = min { print } ' file1 > file2
maht · 639 weeks and 1 day ago
where min and max (inclusive) are the line numbers you're interested in
maht · 639 weeks and 1 day ago
ack my
maht · 639 weeks and 1 day ago
ack my < and > got swallowed (twice !) awk ' NR >= min && NR <= max { print } ' file1 > file2 fingers crossed
maht · 639 weeks and 1 day 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 }
maht · 639 weeks and 1 day ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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