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

Måns Rullgård mru
Tue Dec 5 23:56:41 CET 2006

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

> On 12/6/06, M?ns Rullg?rd <mru at inprovide.com> wrote:
>> "Alexander Chemeris" <ipse.ffmpeg at gmail.com> writes:
>> > 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.
> Fun :)
> My Siemens cable (USB-to-COM inside) work as expected.

This was happening with several brands of USB-serial adapters.  I know
one of them had a Prolific chip inside.

>> > 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
>> used.
> Hummm....
> May be I tweaked it... But I have option "show hidden devices" in Device
> Manager's menu. And if I check it, I see all Flash drives that ever been
> plugged in my computer, unplugged USB-to-COMs and many other fun
> ghosts. Sometimes, when I'm in bad mood, I clean them all.

I didn't know about that option.  I'll have to try it out some time.

>> And don't even think about plugging the thing into a different USB
>> port...
>> Oh well, I guess it's supposed to be user friendly in some way ;-)
> It's a strange way, cause Flash drive is recognized depending on its
> Device Instance Id, without any relation to USB port and device serial num!

Flash drives (or any USB mass storage devices) are funny in another
way too.  Try mapping a network drive to the first non-HD/CDROM
letter, then plug in a USB drive.  Watch in awe and wonder as windows
gives the USB drive the *same* letter as your network drive.

For some more windows fun, find a computer with a builtin flash card
reader connected to internal USB.  Click the "safely remove hardware"
icon, and choose to "remove" the builtin card reader.  Enjoy rebooting
to get it back.

Windows is so much more fun than Linux... always ready with a
surprise to spice up your day.

M?ns Rullg?rd
mru at inprovide.com

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