#!/usr/bin/perl

my $string="testing.123";

my $result = substr( $string, rindex( $string, '.' ) + 1 );

print "$result\n";
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Using this, if $string doesn't have ".123" in it, I get the whole string output, but I don't want that. I just want the string output *if* it has ".123" at the end. I guess what I'm looking for is a test as to whether there's a ".0-9*" expression at the end. I need a ".", then any number of numerical values, but at least one. The "." has to be at the end.