Re^4: Open3 and IO:Select on Win32

Now that's quite a bit different and seems to make more sense. I am now able to get the output I desire but there appears to be some random characters that are printed with the first line. I assume that it'll wait for the process to complete before the shutdown call is made? Or is waitpid needed?

Also, I was checking $fh against $out and $err before (see OP), I don't really seem to have that option now. What can I do to compensate or should I not bother?

sub sys {
my $self = shift;
my $app  = shift;
more();
TRACE "sys > $app @_";
my($pid, $sock) = Win32::Socketpair::winopen2_5($app, @_) or LOGDIE "f
+ailed to open $app: @_";
shutdown $sock, 1;
my ($sel, $buf);
$sel = new IO::Select($sock);
SYSLOOP: while(my @ready = $sel->can_read) {
    foreach my $fh (@ready) {
        my $line = <$fh>;
        if(not defined $line) {
            $sel->remove($fh);
            next;
        }
        $buf .= $line;
    }
}
waitpid($pid, 0);
close $sock;
less();
return $buf;
}
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Re^5: Open3 and IO:Select on Win32 by BrowserUk (Patriarch) on Sep 12, 2014 at 19:49 UTC
Or is waitpid needed? No, though it won't harm. On Windows, when a process terminates the OS stores the return code, so it can be retrieved, and kills the process. Unlike nix where processes hang around as zombies until something asks them for their return code. So on Windows all waitpit does -- assuming the process has actually already completed, which it will have by the time you've read all its output -- is just request the rc from the OS. Also, I was checking $fh against $out and $err before (see OP), I don't really seem to have that option now. What can I do to compensate or should I not bother?* This call doesn't allow you to differentiate between that output that came from stdout and that from stderr -- hence the open2.5. Whilst it would be possible to do a full open3 compatible call, I've never needed it. With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice.	[reply]

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Re^5: Open3 and IO:Select on Win32
by BrowserUk (Patriarch) on Sep 12, 2014 at 19:49 UTC

Or is waitpid needed?

No, though it won't harm. On Windows, when a process terminates the OS stores the return code, so it can be retrieved, and kills the process. Unlike *nix where processes hang around as zombies until something asks them for their return code.

So on Windows all waitpit does -- assuming the process has actually already completed, which it will have by the time you've read all its output -- is just request the rc from the OS.

Also, I was checking $fh against $out and $err before (see OP), I don't really seem to have that option now. What can I do to compensate or should I not bother?

This call doesn't allow you to differentiate between that output that came from stdout and that from stderr -- hence the open2.5.

Whilst it would be possible to do a full open3 compatible call, I've never needed it.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

"Science is about questioning the status quo. Questioning authority".

In the absence of evidence, opinion is indistinguishable from prejudice.

[reply]