Straight out of perldoc -f open:

#              Here is a script that saves, redirects, and restores "S
+TDOUT"
#               and "STDERR" using various methods:

                   #!/usr/bin/perl
                   open my $oldout, ">&STDOUT"     or die "Can't dup S
+TDOUT: $!";
                   open OLDERR,     ">&", \*STDERR or die "Can't dup S
+TDERR: $!";

                   open STDOUT, '>', "foo.out" or die "Can't redirect 
+STDOUT: $!";
                   open STDERR, ">&STDOUT"     or die "Can't dup STDOU
+T: $!";

                   select STDERR; $| = 1;      # make unbuffered
                   select STDOUT; $| = 1;      # make unbuffered

                   print STDOUT "stdout 1\n";  # this works for
                   print STDERR "stderr 1\n";  # subprocesses too

                   close STDOUT;
                   close STDERR;

                   open STDOUT, ">&", $oldout or die "Can't dup \$oldo
+ut: $!";
                   open STDERR, ">&OLDERR"    or die "Can't dup OLDERR
+: $!";

                   print STDOUT "stdout 2\n";
                   print STDERR "stderr 2\n";
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regards,
tomte

Hlade's Law:

If you have a difficult task, give it to a lazy person --
they will find an easier way to do it.

• how do i redirect STDOUT, STDIN, or STDERR to a FILE?
• Restoring STDOUT and STDERR after having redirected them to files

Two of many links found via Super Search and Categorized Questions and Answers

open(STDOUT, ">>log.file"); #open STDOUT and direct into log.file
print "test\n"; #print to STDOUT directed into log.file
close STDOUT;   #close the redirection to STDOUT

open (LOG, "log.file"); #open log.file under a new FileHandle
foreach (<LOG>) { print; } #loop through and print each line.
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