[FFmpeg-devel] [PATCH] Support Ctrl+Break in ffmpeg.exe on Windows as if it was Ctrl+C

[Roger Pack]

On 7/5/12, Michael Niedermayer <michaelni at gmx.at> wrote:
> On Mon, Jun 25, 2012 at 02:21:21PM +0200, Michael Niedermayer wrote:
>> On Tue, Jun 19, 2012 at 07:10:04PM +0200, Reimar Döffinger wrote:
>> > On 19 Jun 2012, at 11:31, Joe Wreschnig <joe.wreschnig at gmail.com>
>> > wrote:
>> > > On Windows, the Ctrl+Break key combination usually does what Ctrl+C
>> > > does. It is more common for processes to send other processes
>> > > Ctrl+Break rather than Ctrl+C, because sending Ctrl+C / SIGINT
>> > > doesn't
>> > > work if you started a child in a new process group.
>> > >
>> > > This patch makes ffmpeg.exe register what Windows calls a console
>> > > control event handler, which allows it to intercept Ctrl+Break. It
>> > > hands it off directly to the usual SIGINT/SIGTERM handler. The same
>> > > function also processes closing the console window, mapping it to
>> > > SIGTERM.
>> > >
>> > > Obviously, this is only enabled if compiling for a platform where
>> > > SetConsoleCtrlHandler is available (i.e. modern Windows).
>> >
>> > What is "modern"? Also it is rather unusual to recompile for different
>> > Windows versions, couldn't you with about the same effort just use
>> > GetProcAddress (more complex code, but in exchange you'd save on all the
>> > configure changes and #ifs).
>>
>> It seems versions that dont support this are no longer supported
>> by microsoft. IMHO we shouldnt bother too much with such old windows
>> versions unless someone wants to / volunteers to do it.
>>
>> thus, if there are no objections i will apply this patch once a few
>> minor issues are fixed (ifdef breaking compile to be precisse)
>
> iam waiting for a working patch
> i could try to fix it before applying myself but with patches for
> non linux platforms i prefer to avoid changing as the changes would
> be untested ,..

Sorry I dropped the ball on this one.
See attached.  The major gains we get out of this (in my head at
least) is hopefully better shutdown if somebody logs out (which has
bitten me before).  Or if someone closes a console window which also
shuts down FFmpeg.

I noticed that even with handling notifications of "logout" that
ffmpeg can still easily leave behind corrupted mp4 files (it gets
killed quickly after).
Makes me wonder if there's some way to make it shutdown more quickly,
but I'm not sure if it's a problem yet or not.
Cheers!
-roger-
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