one liner based on suaveant's code above...  perl -pi -e's/([A-Z]{4,})/___$1___/g; $_ = lc; s/___([a-z]{4,})___/uc($1)/ge' filename

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

In reply to Re: upper/lowercase search/replace by Beatnik
in thread upper/lowercase search/replace by Prince99

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