#!/usr/bin/perl -w
use POSIX qw/locale_h/;

my $orig_loc = setlocale( LC_ALL );
my $loc;
open my $LOCALES, '-|', 'locale -a';
local $\ = "\n";
print "The following locales use comma as decimal point";
while (<$LOCALES>) {
    chomp;
    $loc = setlocale( LC_ALL, $_);
    print $_ if localeconv()->{decimal_point} eq ',';
}
close $LOCALES;
$loc = setlocale( LC_ALL, $orig_loc);