• If you're starting a new project then you should look at something like Log::Log4perl.
• A quick 'n' dirty solution is to just run your program redirecting output to a file (i.e ./my_prog > some_file.log).

You can also duplicate the STDOUT file handle as described in perlopentut or open.

This is a good idea. Windows systems don't have tee, I hacked in this tee.pl awhile ago for my Windoze work. It is a simple program. The only tricky part is turning auto-flush on for write. Have fun to anybody who needs it.

#!/usr/bin/perl -w
use strict;

# tee program ####  tee.pl ######
# quickie tool 

$| =1;   #flushes I/O for each write.

sub usage  
{
   print "TEE USAGE:\n tees stdout to a file and to stdout\n".
      " program | tee outfile\n";
}

my $filename = shift @ARGV;
usage unless $filename;

open (OUTFILE, '>', "$filename") or (die "Can't open OUTFILE: $!");

while (<>)
{
   print;
   print OUTFILE;
}
[download]

You can open your log-file at the start of your program and just write to it with the print statements:

my $logfile = 'path/to/logfile.txt';
open(LOG, "> $logfile") or die "could not open log-file: $!";

print LOG "this is a log entry\n";
[download]

If you need to see your log output immediately be aware of buffering issues ...

cheers

si_lence