[Ffmpeg-devel] [PATCH] Correct inttypes.h emulation for VisualStudio

Måns Rullgård mru
Tue Dec 5 23:29:02 CET 2006

"Alexander Chemeris" <ipse.ffmpeg at gmail.com> writes:

> Hello,
> On 12/6/06, M?ns Rullg?rd <mru at inprovide.com> wrote:
>> Corey Hickey <bugfood-ml at fatooh.org> writes:
>> > M?ns Rullg?rd wrote:
>> >>> There's a computer where I work that has two onboard serial
>> >>> ports. Windows calls them both COM2, and it can't use either of them.
>> >> It's sometimes possible to change the numbering from the device
>> >> manager.
>> > At the time, as far as I could tell, changing it within the device
>> > manager was not possible (I did look, but I don't remember the
>> > details). I just plugged in a USB-->serial adapter and used that
>> > instead.
>> What annoys be with USB-serial adapters in windows is that each time
>> you plug it in, the COM number gets incremented, soon becoming
>> inaccessible from programs that only offer a choice of COM1-4, and
>> eventually stops working entirely when it reaches some maximum value.
> Not exactly. Windows assigns COM port number to pair "USB port + Adapter
> serial number". So if you plug same adapter to the same USB port it set
> the same COM port number. :)

That's probably how it's supposed to work, but it doesn't actually.
I've seen the very same USB-serial adapter be assigned ever increasing
numbers each time it's been plugged in.

> And if you overloaded with adapter instances, you could delete unused ones
> in Device Manager. And thier COM port numbers will be freed and used
> if you plug other adapter or the same adapter to other port.

They don't show up in the device manager so there's no way to delete
them.  The only trace of those numbers is in the dialog for assigning
port numbers to serial devices, where the old numbers are marked as

And don't even think about plugging the thing into a different USB

Oh well, I guess it's supposed to be user friendly in some way ;-)

M?ns Rullg?rd
mru at inprovide.com

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