missing pieces for a SDL-like library

[Cosmin Apreutesei]

[I'll dump more questions here so that I don't create too many
conversation threads if that's ok]


- Is there an XAppFocusOut event similar to Windows WM_ACTIVATEAPP[1]
or OSX applicationDidResignActive[2] ?


[1] https://msdn.microsoft.com/en-us/library/windows/desktop/ms632614(v=vs.85).aspx
[2] https://developer.apple.com/library/mac/documentation/Cocoa/Reference/NSApplicationDelegate_Protocol/#//apple_ref/occ/intfm/NSApplicationDelegate/applicationDidResignActive: