You have to obtain the handle of the window you want focus in then call set focus on that handle. From Gtk+ in X I can do this:

XRaiseWindow(GDK_DISPLAY(), (Window) x_win);
XSetInputFocus(GDK_DISPLAY(), (Window) x_win), RevertToParent,
CurrentTime);
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Gentle reminder: When posting snippets of code to PM they look nicer if you put < code></code> around the snippit. Like this:

$ppc = Win32::Process::Create(
    $global_process, 
    $command_a, 
    $command_b, 
    0, 
    NORMAL_PRIORITY_CLASS, 
    '.'
);
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