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How do I determined, whether Xorg is using Xinerama, DDC and Reduced Blanking ??

Just adding few options in Xorg.conf is sufficient ?

If I have to check from command-line, then how can I check above mentioned settings ?

(I am using VIA chipset and Dell DELA07A monitor, Just in case this info required )


If I execute the command: Xorg -extension ? It gives me the output as

[mi] Extension "?" is not recognized
[mi] Only the following extensions can be run-time disabled:
[mi]    Generic Events
[mi]    Composite
[mi]    DAMAGE
[mi]    DPMS
[mi]    GLX
[mi]    MIT-SHM
[mi]    RANDR
[mi]    RENDER
[mi]    SECURITY
[mi]    X-Resource
[mi]    XFIXES
[mi]    XINERAMA
[mi]    SELinux
[mi]    XTEST
[mi]    XVideo

As per the above output, I assume that it is possible to enable/disable extensions in runtime. Question is HOW ? If it is really possible then I can enable/disable the XINERAMA extension as and when I want

I also assume that when XINERAMA is ON in dual-head then maximizing an open application will span on both monitor. And when XINERAMA is off then maximizing an application will span to one monitor only. ( Correct me if I'm wrong )

share|improve this question
cat /var/log/Xorg.0.log (for display :0). See also xdpyinfo for some information. – Stéphane Chazelas Nov 1 '13 at 13:10
xdpyinfo | egrep -i 'Xinerama|DDC|Reduced Blanking' returns XINERAMA here. – Teresa e Junior Nov 1 '13 at 19:13

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