uc

See the current Perl documentation for uc.

Here is our local, out-dated (pre-5.6) version:

uc - return upper-case version of a string

uc EXPR

uc

Returns an uppercased version of EXPR. This is the internal function implementing the \U escape in double-quoted strings. Respects current LC_CTYPE locale if use locale in force. See the perllocale manpage.

If EXPR is omitted, uses $_.