Bug#589839: /usr/bin/xgamma: can only set gamma on one screen

["Michal Suchanek" <michal.suchanek@ruk.cuni.cz>]

Excerpts from Julien Cristau's message of Wed Jul 21 17:38:49 +0200 2010:
> On Wed, Jul 21, 2010 at 16:52:21 +0200, Michal Suchanek wrote:
> 
> > Package: x11-xserver-utils
> > Version: 7.5+1
> > Severity: normal
> > File: /usr/bin/xgamma
> > 
> > 
> > In multi-screen configuraion the gamma can be set only on the first
> > screen. It is not obvious how to set gamma on the other screen(s), the
> > format of the -s option is not specified.
> > 
> I'm not sure what you're trying to say.  To set gamma on screen 0, you
> use xgamma -screen 0. 

Which sets gamma on the secondary screen when it is on or on the
primary screen when the secondary is off.

> To set gamma on screen 1, use xgamma -screen 1.

Which gives an X error:
X Error of failed request:  BadValue (integer parameter out of range for
operation)
  Major opcode of failed request:  129 (XFree86-VidModeExtension)
  Minor opcode of failed request:  16 (XF86VidModeGetGamma)
  Value in failed request:  0x17
  Serial number of failed request:  12
  Current serial number in output stream:  12

Thanks

Michal
-- 
Michal Suchánek
michal.suchanek@ruk.cuni.cz
tel 224491810 fax 224491594
Univerzita Karlova v Praze
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