In my office and home, my main working machines run Linux, connected to dual displays. But I also use a third monitor to connect my MacBook Pro, mostly used for reading articles, browsing web, and such time-wasting endeavors. So altogether I use four monitors all the time, three big ones and the laptop’s internal display. I use Synergy to connect a mouse and a keyboard to both the Mac laptop and the Linux desktop.
I noticed that I really don’t need the laptop’s internal display to be on. It’s smaller than the other three and the reflective screen, while not troublesome when viewing solo, is a major distraction while using simultaneously with non-reflective bigger screens. So I was searching for a way to switch off the laptop’s internal display, keeping only one external display on.
Those of you who are accustomed with using MacBook attached to an external display will immediately jump up and say just close the laptop’s lid. Both internal and external displays will go to sleep. Then just press any keyboard key or move the mouse, and only the external display will turn on. Not so fast.
The problem is that the laptop is not connected to any keyboard or mouse. They are actually connected to the desktop. The laptop is simply a client of the Synergy server. You might say, just use laptop as Synergy server and desktop as client. This is not really a prudent thing to do. If I forget the laptop at home, I have to reconnect all those USB cables.
Suddenly, the solution fell on my lap (laptop?). The laptop was in sleep, and my iPhone was running out of juice. I simply connected the iPhone with an USB cable to the sleeping laptop, and ahem, the laptop woke up, the external display flickered on, and behold, the internal display was still off. So, just connect any USB device to a sleeping Macbook Pro, attached to an external monitor, and you can just use only the external display. I suggest keeping the lid open though, otherwise you might have to call 911.