Hi, I'm currently trying to port a project over from linux to Windows and hit a bit of a snag when using Open3 and IO::Select to read both STDOUT and STDERR.

It appears that if I dump the select handle I never see STDERR get set and I never got into my loop because can_read is never ready. I'm not quite sure of how to work around this on Windows and could really use some help!

sub sys {
my $self = shift;
my $app  = shift;
my ($pid, $in, $out, $err, $sel, $buf);
$err = gensym();
more();
TRACE "sys > $app @_";
$pid = open3($in, $out, $err, $app, @_) or LOGDIE "failed to open $app
+: @_";
$sel = new IO::Select;
$sel->add($out, $err);
SYSLOOP: while(my @ready = $sel->can_read) {
    foreach my $fh (@ready) {
    my $line = <$fh>;
    if(not defined $line) {
        $sel->remove($fh);
        next;
    }
    if($fh == $out) {
        TRACE "sys < $line";
        $buf .= $line;
    }
    elsif($fh == $err) {
        TRACE "sys !! $line";
        $buf .= $line;
    }
    else {
        ERROR "Shouldn't be here\n";
        return undef;
    }
    }
}
waitpid($pid, 0);    
less();
return $buf;
}

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Using strawberry perl 5.18.1.1 64bit on Windows 7 x64.

In reply to Open3 and IO:Select on Win32 by Elegant

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