in reply to Printing with Indirect FileHandles

update: revised to recognize the evidence of your last example.

print says print only prints $_ if neither a filehandle nor an argument list is provided, except that your last example demonstrates that it does not behave exactly as print says it does.

You could use the following:

use strict;
use warnings;
open( my $output, '>', '/tmp/output.txt' )
    or die "Error: Cannot open the file - $!\n";

open( my $input, '<', '/tmp/input.txt' )
    or die "Error: Cannot open the  file - $!\n";

select $output;
print while (<$input>);   ## This is were the problem is.

close( $input );
close( $output );

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Re^2: Printing with Indirect FileHandles
by ikegami (Patriarch) on Aug 26, 2009 at 00:54 UTC

    except that your last example demonstrates that it does not behave exactly as print says it does.

    How so?

    In print {$output} $_, nothing is omitted, so what is specified to print is printed to the specified handle.

    In print $output $_, nothing is omitted, so what is specified to print is printed to the specified handle.

    In print $output, the file handle is omitted, so $output is printed to the currently selected handle.

    And the first, print {$output}, is not one of the valid forms.

[reply]
[d/l]
[select]

      In print OUTPUT while (<$input>); a file handle is given but no list. print doesn't even admit in the synopsis that such a case is possible and it says:

      If LIST is also omitted, prints $_ to the currently selected output channel.

      My emphasis.

[reply]
[d/l]
        oh, I missed that one.
[reply]
      Thanks. And what is the explanation as to why print OUTPUT works?
[reply]

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