[PATCH] Add configuration option for use of SIGIO handlers for input events

[Peter Hutterer]

On Sat, Sep 12, 2009 at 08:52:00AM -0700, Alan Coopersmith wrote:
> Peter Hutterer wrote:
> > Do you plan to make this a permanent option or just for the meantime?
> > If it is just for the meantime, I'd prefer some warnings with both the
> > --enable-sigio option and the xorg.conf option that this is not considered a
> > stable configuration and may be ignored in the future.
> 
> I hadn't thought about making it temporary - though I wasn't planning on
> documenting it in the xorg.conf man page since users shouldn't be using
> it except when told by a developer it's needed to workaround a particular
> bug.   

Document it in the man page please with exactly that warning.
Undocumented on purpose looks the same as undocumented ouf of forgetfulness.
All it takes is one user to "feel" that the server is better/faster/more
reponsive/made of chocolate when this option is on and suddenly you find
hundreds of forum posts recommending this everywhere.

I still see configurations with AllowEmptyInput off because there was a
brief period when that fixed a certain broken setup. Now people use it
because they read it somewhere and thought it's a good idea.

Cheers,
  Peter

> At this point, we're likely to get the fixes needed in Solaris
> kernel/libraries for OpenSolaris & future Solaris releases, but not backport
> to older Solaris releases, so we'll probably need to leave it in as a
> configure option as long as Xorg supports building on Solaris 10, which is
> likely to be many more years.   (I just dropped Solaris 7 and older about
> a month ago, and from the bug reports I think Solaris 8 still has a build
> error, but it's been a few years since I tried building that myself.
> Solaris 10 is our current supported enterprise release though.)