How Do I Point a File Handle to STDOUT (or Another File Handle) In Perl?

Question

I want to make a quick script that writes to a file if a file is given, or stdout if no file is given. It would be much easier for me to do this if I could start the script by p

Answer 1

Some ways (globs):

# Requires 2-arg open, unfortunately
open(OUTPUT, "> ".($output || '-'))  or die;

if ($output) {
   open(OUTPUT, '>', $output) or die;
} else {
   *OUTPUT = *STDOUT;
}

if ($output) {
   open(OUTPUT, '>', $output) or die;
} else {
   open(OUTPUT, '>&', \*STDOUT) or die;
}

Some ways (lexical var):

# Requires 2-arg open, unfortunately
open(my $fh, "> ".($output || '-'))  or die;

my $fh;
if ($output) {
   open($fh, '>', $output) or die;
} else {
   $fh = \*STDOUT;
}

my $fh;
if ($output) {
   open($fh, '>', $output) or die;
} else {
   open($fh, '>&', \*STDOUT) or die;
}

Some ways (other):

# Changes the default handle for .
if ($output) {
   open(OUTPUT, '>', $output) or die;
   select(OUTPUT);
}