Re: Grabs on Win32 (Was: [Gimp-developer] Screenshot plug-in status)

["J. Ali Harlow" <ali avrc city ac uk>]

On 2003.09.07 12:50 Tor Lillqvist wrote:

> Also, the PSDK docs say:
>
>   Note: You should use global hooks only for debugging purposes;
>   otherwise, you should avoid them. Global hooks hurt system
>   performance and cause conflicts with other applications that
>   implement the same type of global hook.
>
> which kinda suggests to me that it would not be a good idea to set and
> unset global hooks for things like pointer grabs, which GTK seems to
> use quite often.
>
> Comments, please?

I wouldn't claim to be an expert but I use Hooks to trace third
party program execution. They are a serious resource hog which
is quite likely to reduce the stability of the whole machine. As
I understand it, the first time the hook is actioned for each
process the relvant DLL will be mapped into that process' address
space and the hook called. If that DLL was gdk that would be
a really bad idea and cause all sorts of problems with processes
which already have gdk mapped or will presently map gdk. It would
be better to use a small helper DLL, but I still think the whole
idea is a non-starter. Sorry.

--
Ali Harlow                              Email: ali avrc city ac uk
Research programmer                     Tel:   (020) 7040 4348
Applied Vision Research Centre          Intl: +44 20 7040 4348
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