OS X 10.10 Source code posted

Discussion in 'OS X Yosemite (10.10)' started by Mactaculious, Oct 17, 2014.

  1. Mactaculious macrumors regular

    Oct 6, 2014
    Anyone know how to turn off the Macbook pro display with the lid open while using external monitors on Mac OS X 10.10 Yosemite?

    (I am aware that you can just close the lid, but I want to keep this open for air flow purposes and turning down the brightness is not the same as turning the display off as the GPU still sends a signal to the display thus uses more battery and creates more heat.)

    On Mavericks this worked just fine as mentioned in the link:



    Here is a terminal command thats fairly simple that will allow you to keep the lid open for adequate cooling but while using the external display only. I've been using this method with my Thunderbolt display and MacBook Air since the beta of Mountain Lion came out and it works perfect. Has all the same characteristics of good old clamshell mode. Be sure to keep this written down someplace in the off chance you need to re-install, do a PRAM reset, or just want to undo it.

    To execute in Terminal:

    sudo nvram boot-args="iog=0x0"

    To undo in Terminal:

    sudo nvram -d boot-args

    Once you type it into terminal I believe you need to enter your password. I then restart my machine. Now the TRICK is to either restart your machine with the lid already closed (hit restart then slam the lid!) OR turn the machine on for the first time (then quickly slam the lid!) once you are past the login screen you can open the lid.
  2. Mactaculious thread starter macrumors regular

    Oct 6, 2014
  3. Watabou macrumors 68040


    Feb 10, 2008
    United States
    Firstly, the source code doesn't help with this in any way. Secondly, Apple only releases the source code of the low-level layer (like the kernel, shell, utilities) but not the GUI layer.

    Finally, doesn't the nvram trick work?

    Type this into the Terminal:
    sudo nvram boot-args="iog=0x0"

    If you want to undo this, just zap the PRAM.

    If you want a link: http://osxdaily.com/2011/09/14/disa...n-a-macbook-pro-or-air-in-mac-os-x-10-7-lion/
  4. gumblecosby macrumors 6502

    Jun 22, 2010
    Only certain parts of OS X are open source. WindowServer/Quartz isn't , sadly for us.

    Watabou's tip does work for me but I have to boot the Mac with the lid closed.
    -> Connect the Mac to your external display, push the power button and then immediately close the lid and wait till it reaches the desktop/login screen.

    After doing this successfully, the usual trick of closing the lid and connecting a mouse should work like normal.

    A caveat: certain models just do not work with this. Hopefully yours isn't one of them
  5. Mactaculious thread starter macrumors regular

    Oct 6, 2014
    Tried this already, this does not work for me anymore like it did on Mavericks.


    Yes, unfortunately mine is one of them, while this worked perfectly on Mavericks this no longer works on Yosemite. Running a late 2013 model. :(
  6. Mactaculious thread starter macrumors regular

    Oct 6, 2014
  7. Tankmaze macrumors 68000


    Mar 7, 2012

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