Hello pedrete

A oneliner? 

# windows double quotes
perl -lne "$mark++ if /MyWantedTextMark/; print if $mark" a.txt  > b.t
+xt

# Linux quotes
perl -lne '$mark++ if /MyWantedTextMark/; print if $mark' a.txt  > b.t
+xt

[download]

See perlrun where perl switch are described

L*

There are no rules, there are no thumbs..
Reinvent the wheel, then learn The Wheel; may be one day you reinvent one of THE WHEELS.

In reply to Re: Fastest way of changing the beginning of a txt file.. -- oneliner by Discipulus
in thread Fastest way of changing the beginning of a txt file.. by pedrete

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