Win32::Process::Create creates processes, not threads. You might think that this is semantics, but the distinction is important - you will just confuse everyone if you talk about threads when you mean processes. If you are not sure of the difference, threads are several concurrent paths of execution within the same process, and require specialised techniques (not to mention the odd pagan incantation).

Meanwhile, back at your code, ikegami suggested some solutions, although you have a couple of problems with your code.

Your $perl_command has single back-slashes in it, which 'escapes' the character which follows (gives it a special meaning, or removes a special meaning if it had one). You did it right in the second parameter to Win32::Process::Create by using \\.

You should always test your return value when you can - if you get the chance to trap an error then take it!

Finally, you might find it easier to use the comspec environment variable to give you the path to the shell.

Here are my suggestions with modifications adapted to run on my system (you will have to alter the paths, watch those \):

#!/usr/bin/perl
use strict;
use Win32;
use Win32::Process;

my $ProcessObj;
my $perl_command = '';

print "Starting thread logging test\n";

$perl_command = "$ENV{comspec} /c C:\\perl\\bin\\perl.exe C:\\output_t
+est.pl >MyLog.txt 2>&1";

print "\n$perl_command\n";

my $result = Win32::Process::Create($ProcessObj,$ENV{comspec},$perl_co
+mmand,1,CREATE_NO_WINDOW,".");

if ($result == 0) {
    die "Error: ",Win32::FormatMessage( Win32::GetLastError() ),"\n";
}

print "Thread logging test completed\n";
[download]

By the way, you shouldn't really need a shell to do this redirection for you. The C/C++ Win32 API CreateProcess has a struct within it which includes handles for stdin, stdout and stderr of the child process. It is a great shame that the implementor of Win32::Process::Create chose to omit these.