perl -pi.bak -e'if (!/^s/) { $_ = "" }' filename in shell

Greetz
Beatnik
... Quidquid perl dictum sit, altum viditur.

In reply to Re: Wish to keep only those lines which start with letter s, and delete all other lines. by Beatnik
in thread Wish to keep only those lines which start with letter s, and delete all other lines. by Anonymous Monk

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