#! /usr/bin/perl -w

use strict;

# use all the modules I'm using in the main script, just in case
use DBI;
use File::Basename  qw/basename/;
use File::Path      qw/mkpath/;
use Getopt::Mixed;
use IO::File;
use IO::Tee;

my $max = shift || 3;

BEGIN {
    my @now;
    sub work_name {
        @now = localtime unless @now;
        sprintf(
            '/var/log/test/%02d%02d%02d.log',
            sub{ @_[reverse 0..2] }->(@now)
        )
    }
}

my $logger = do {
    my $logfile = work_name();
    my $fd = new IO::File( "> $logfile" )
        or die "Could not open $logfile for output: $!\n";
    new IO::Tee(\*STDOUT, $fd );
};
END { $logger and $logger->flush and $logger->close }

for( 1..$max ) {
        my $letter = ('a'..'z')[rand 26];
        my $lines = 1 + int(rand(10));
        my $cols  = 1 + int(rand(72));
        $logger->print( "$_ ", (($letter x $cols) . "\n") x $lines );
}
$logger->print("--end--");
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I thought it might have been problems with a missing \n on the last line, or needing to flush explicitly, but that doesn't change things. The test script works, but not the main script. Elsewhere in the script I am using arrays of arrays of IO::File objects which behave as advertised. At no point do I do any bare prints (to STDOUT), everything is printed via the logger object.

If, in the main script, I create the $logger object, print to it and exit immediately, the output gets recorded in the log file. Something down the track seems to be making things go haywire, and I am at a loss as to explain why. I am using 5.6.0, which is the most suspicious thing I can think of. For instance, I am not using sfio.

Any tips or suggestions for things to try are most appreciated.