File::Basename is easier:
use warnings;
use strict;
use File::Basename;
my $file = 'http://txs.corp.com:8080/area/es/2215.csv.gz';
my $gzip = basename($file, qr/\.gz/);
print "$gzip\n";
__END__
2215.csv.gz
Demystify regular expressions by installing and using the CPAN module YAPE::Regex::Explain (Tip #9 from Basic debugging checklist)
The regular expression:
(?-imsx:/(.*?\.gz)$)
matches as follows:
NODE EXPLANATION
----------------------------------------------------------------------
(?-imsx: group, but do not capture (case-sensitive)
(with ^ and $ matching normally) (with . not
matching \n) (matching whitespace and #
normally):
----------------------------------------------------------------------
/ '/'
----------------------------------------------------------------------
( group and capture to \1:
----------------------------------------------------------------------
.*? any character except \n (0 or more times
(matching the least amount possible))
----------------------------------------------------------------------
\. '.'
----------------------------------------------------------------------
gz 'gz'
----------------------------------------------------------------------
) end of \1
----------------------------------------------------------------------
$ before an optional \n, and the end of the
string
----------------------------------------------------------------------
) end of grouping
----------------------------------------------------------------------