Support special --position arguments for screen centre and edges about mintty HOT 4 OPEN

here is a diff...

$ diff winmain.c winmainx.c
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>   "  -x, --center          Open window in center of screen\n"
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< static const char short_opts[] = "+:HVuec:o:p:s:w:t:i:l:h:";
---
> static const char short_opts[] = "+:HVeuxc:o:p:s:w:t:i:l:h:";
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>   {"center",   no_argument,       0, 'x'},
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>   bool center = false;
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>       when 'x': center = true;
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>
>   if (center) {
>     static RECT ss;
>     get_fullscreen_rect(&ss);
>     SetWindowPos(wnd, null,
>                  (ss.right - (term_width + extra_width + 2 * PADDING))/2,
>                  (ss.bottom - (term_height + extra_height + 2 * PADDING))/2,
>                  term_width + extra_width + 2 * PADDING,
>                  term_height + extra_height + 2 * PADDING,
>                  SWP_NOZORDER);
>   }

Good work, but no, I wouldn't want to add this as a separate option. However, I 
could imagine adding it as a special argument to the --position option, along 
with support for the four edges, so you could say something like 
'--position=right,top' or '-position=centre,centre'.

I'm not really convinced that this is necessary though, because the existing 
--position functionality already supports these use cases; it's just that it 
might require a bit of experimentation to find the right coordinates.

I agree that adding to the existing -p option is better, my current c skills 
would not let me go there without actually looking something up!  This was for 
a script that gets kicked off after an install, so who knows what res screen it 
would run on, and folks wanted it centered like the installer that came before 
it.

Thanks, that's a valid new use case (although perhaps not a very common one).