You'll find that $ENV{'PATH_INFO'} holds what you're looking for.

And %ENV has more interesting information, so dumping it is not a bad idea:

#!/usr/bin/perl -w
use Data::Dumper;

print "\n"; # The shortest CGI header possible,
            # the server will assume text/plain.
print Dumper \%ENV;
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Or, without Data::Dumper:

#!/usr/bin/perl -w
print map "\n$_ => $ENV{$_}", keys %ENV;
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