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Top Forums Shell Programming and Scripting sed command explanation needed Post 302090520 by subbukns on Tuesday 26th of September 2006 08:34:54 AM
Old 09-26-2006
sed command explanation needed

Hi,

Could you please explain me the below statement -- phrase wise.

sed -e :a -e '$q;N;'$cnt',$D;ba' abc.txt > xyz.txt


if suppose $cnt contains value: 10
it copies last 9 lines of abc.txt to xyz.txt

why it is copying last 9 rather than 10.
and also what is ba and $D over there in command.

reply me as early as possible.

Thanks,
Subbu
 

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