http://www.perlmonks.org?node_id=11128969


in reply to Three argument version of open '>-' (updated)

Maybe try open $fh, '>&', STDOUT;

behavior looks consistent when autoflush is activated.

Otherwise please use a similar code-template for a SSCCE.

use v5.12; use warnings; use Data::Dump qw/pp dd/; sub tst { my $vers = shift; open STDOUT, ">-"; # restore STDOUT $|=1; say STDERR "********* testing $vers\n"; my $fh; open $fh, ">-" if $vers eq "open2"; $fh = \*STDOUT if $vers eq "copyref"; open $fh, '>&', STDOUT if $vers eq "redirect"; $fh->autoflush; say "$vers 1"; close STDOUT; say $fh "$vers 2"; say "$vers 3"; } tst("redirect"); tst("open2"); tst("copyref");

-*- mode: compilation; default-directory: "d:/tmp/pm/" -*- Compilation started at Mon Mar 1 23:21:00 C:/Strawberry/perl/bin\perl.exe -w d:/tmp/pm/redirect_STDOUT.pl ********* testing redirect redirect 1 redirect 2 say() on closed filehandle STDOUT at d:/tmp/pm/redirect_STDOUT.pl line + 32. ********* testing open2 open2 1 open2 2 say() on closed filehandle STDOUT at d:/tmp/pm/redirect_STDOUT.pl line + 32. ********* testing copyref copyref 1 say() on closed filehandle STDOUT at d:/tmp/pm/redirect_STDOUT.pl line + 30. say() on closed filehandle STDOUT at d:/tmp/pm/redirect_STDOUT.pl line + 32. Compilation finished at Mon Mar 1 23:21:00

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

Replies are listed 'Best First'.
Re^2: Three argument version of open '>-'
by choroba (Cardinal) on Mar 01, 2021 at 23:06 UTC
    OP updated witn a SSCCE.

    map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]
      Thanks, it's clearer now, you want that the "copy FH" fails if STDOUT is closed, but without emitting a warning.

      Sorry, no clue yet...

      update

      BTW: you can automatize your test-runs with an exec $0 #Test if @ARGV is empty :)

      and maybe you should also consider testing different states of autoflush.

      Cheers Rolf
      (addicted to the Perl Programming Language :)
      Wikisyntax for the Monastery