It don't see it as a problem with locales. For example, try this: 
#!/usr/bin/perl -l

use strict;
use warnings;

my $num = 123.456;
str($num);

sub str {
   my ($want_num, $width) = @_;
   $width = '000';
   $want_num =~ tr/./,/;
   $want_num = print "$want_num$width";
}

[download]
Does that work for you?

In reply to Re: Perl, Gtk2 and locale — a bit of a mess by Khen1950fx
in thread Perl, Gtk2 and locale — a bit of a mess by Ralesk

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