Resisting the temptation to say "Silly boy!", change quotes to suit. 

perl -ple"/^</root>/ and map{ scalar <> } 1..3" file.xml >new.xml

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Examine what is said, not who speaks.        The end of an era!
"But you should never overestimate the ingenuity of the sceptics to come up with a counter-argument." -Myles Allen
"Think for yourself!" - Abigail        "Time is a poor substitute for thought"--theorbtwo         "Efficiency is intelligent laziness." -David Dunham
"Memory, processor, disk in that order on the hardware side. Algorithm, algorithm, algorithm on the code side." - tachyon

In reply to Re: Replacing Lines in 100 Gig file by BrowserUk
in thread Replacing Lines in 100 Gig file by Anonymous Monk

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