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sed one liner simialr to tail command

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# 1  
Old 12-28-2011
sed one liner simialr to tail command
Can anyone explain the below sed oneliner?
Code:
sed -e ':a' -e '$q;N;11,$D;ba'

It works same as tail command.
I just want to know how it works.
Thanks
# 2  
Old 12-28-2011
The -e ":a" defines a label at the start of the sed programme.

The second part of the programme breaks down like this:
Code:
$q;     # when end of file is reached, print the pattern space and quit
N;      # read the next line from input and append to pattern space
11,$D; # for all input lines from 11 until the end of the file, 
         #delete up to the first newline (keeps the last 10 lines in the pattern space)
ba      # branch to label a which is the start (prevents printing the pattern space)

This User Gave Thanks to agama For This Post:
pandeesh
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