G'day JimSi,

use loads modules at compile time. For your variable to work as expected, it would need to initialised also at compile time and prior to calling use.

You haven't shown the code that failed. Is it something like this (I'm just using the BEGIN block to emulate your use statement):

#!/usr/bin/env perl -l

use strict;
use warnings;

my $host = 'localhost';

BEGIN {
    print 'Host: ', $host;
}
[download]

Producing output like:

$ pm_1125079_begin_before_use.pl
Use of uninitialized value $host in print at ./pm_1125079_begin_before
+_use.pl line 9.
Host:
[download]

Here's how you could fix that:

#!/usr/bin/env perl -l

use strict;
use warnings;

my $host;
BEGIN {
    $host = 'localhost';
}
BEGIN {
    print 'Host: ', $host;
}
[download]

Which now outputs the wanted value:

$ pm_1125079_begin_before_use.pl
Host: localhost
[download]

That may lead you to a solution. If it doesn't, please post the actual code that is failing as well as all output you receive. Guidelines for what information to post with your question can be found at: How do I post a question effectively?.