Re: shell redirect on windows, qx?

[BrowserUk]

in reply to shell redirect on windows, qx?

This is perl 5.8.6/AS811 on XP:

c:\test>perl
use File::Temp qw( tempfile );
use File::Spec qw( devnull );
$|=1;

my $code =<<'CODE';
  $|=1;
  print "ABC\n";
  print STDERR "012\n";
  print "IJK\n";
  print STDERR "345\n";
  print "XYZ\n";
  print STDERR "678\n";
CODE

# create a temporary perl script file
my ($fh1, $scriptname) = tempfile( 'yap_XXXX', SUFFIX => '.pl');
print {$fh1} $code;
close( $fh1 );

my $perl = $^X;
my $devnull = File::Spec->devnull;
print "No redirect: \n";
print qx{ $perl $scriptname }, "\n";
print "Redirect errors to devnull: \n";
print qx{ $perl $scriptname 2>$devnull }, "\n";
print "Redirect merging stderr and stdout: \n";
print qx{ $perl $scriptname 2>&1 }, "\n";
^Z
No redirect:
012
345
678
ABC
IJK
XYZ

Redirect errors to devnull:
ABC
IJK
XYZ

Redirect merging stderr and stdout:
ABC
012
IJK
345
XYZ
678

[doom]

Ah, cool. It looks like Active State perl behaves very much like a unix-box in this respect. Thanks for the reply.

[BrowserUk]

It looks like Active State perl behaves ...

It's not down to AS perl. The redirection is done by the shell processor that is invoked by qx/backticks or system. Under AS perl that shell is the standard win32 cmd.exe.

Other variants, such as cygwin builds and Strawberry etc. may choose to invoke a different shell. I think cygwin (as standard) uses a sh-alike, but you can probably get csh, bash or zsh that would run under cygwin. (If you must:), but you might have to configure something somewhere to get them used by default, and each has its own set of advantages and restrictions as with the *nix brethren.

In theory, there is nothing to stop you from configuring a cygwin build to use cmd.exe, but I've no idea how.