qmake platform scopes

Question

A standard c++ qmake-based library is developed for Win32, Mac, and Linux. In the qmake project file, the platform-dependent sources are included like this:

Answer 1

You can negate and combine blocks, so in unix but not in mac would be:

unix:!macx {
  SOURCES += LinuxSystem.cpp
  HEADERS += LinuxSystem.h
}