How to run sdl-config in a Qt Project

I did a quick google search for this and didn't find anything so I thought I would figure it out myself. It is actually quite easy, you need to use the $$system() function in qmake to run the sdl-config script (which should be in your path) and then assign it to the correct qmake variables. The following code snippet shows what to add

LIBS+=$$system(sdl-config  --libs)
message(output from sdl-config --libs added to LIBS =$$LIBS)
CXX_FLAGS+=$$system(sdl-config  --cflags)
message(output from sdl-config --cflags added to CXX_FLAGS= $$CXX_FLAGS)

The message calls are there to display the output for debug and can be removed. This will output the following (on my mac)

Project MESSAGE: output from sdl-config --libs added to LIBS =-L/usr/local/lib -lSDLmain -lSDL -Wl,-framework,Cocoa
Project MESSAGE: output from sdl-config --cflags added to CXX_FLAGS= -I/usr/local/include/SDL -D_GNU_SOURCE=1 -D_THREAD_SAFE