Here is a test that I set up that seems to be working, but I do not fully understand why. I removed the logging facility from module 1 and placed it into its own utility module. I'm confused in TestUtil.pm--why isn't redeclaring or reopening $LOG an issue? I assume the calls are entirely separate from each other? Even still, why are there no file conflicts?

test.pl

#!/usr/bin/perl
use warnings;
use strict;

use TestMod1;
use TestMod2;
use TestUtil;

print "in file.\n";
write_log('file');
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TestMod1.pm

#!/usr/bin/perl
package TestMod1;
use warnings;
use strict;
use TestUtil;

print "loaded Mod1\n";
write_log('Mod1');

1;
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TestMod2.pm

#!/usr/bin/perl
package TestMod2;
use warnings;
use strict;
use TestUtil;

print "loaded Mod2\n";
write_log('Mod2');

1;
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TestUtil.pm

#!/usr/bin/perl
package TestUtil;
use strict;
use warnings;

require Exporter;

our @ISA = qw(Exporter);
our @EXPORT = qw(write_log);

print "loading module TestUtil\n";

#our $LOG if not $LOG and print "LOG did not exist.\n";
our $LOG;

open $LOG, '>', 'test.log' or die;
print "\$LOG = $LOG\n";

sub write_log {
        my $string = shift;
        print $LOG "$string\n";
}

1;
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test.log

Mod1
Mod2
file
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screen output

loading module TestUtil
$LOG = GLOB(0x4006fcd4)
loaded Mod1
loaded Mod2
in file.
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