/usr/include/ClanLib-1.0/ClanLib/Core/System/ is in libclanlib-dev 1.0~svn3827-3build1.
This file is owned by root:root, with mode 0o755.
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/usr/include/ClanLib-1.0/ClanLib/Core/System/call_stack.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/cl_assert.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/cl_library.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/clanstring.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/clipboard.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/clonable.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/command_line.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/console_window.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/crash_reporter.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/error.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/event_listener.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/event_trigger.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/keep_alive.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/lazycopyptr.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/log.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/mutex.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/mutexsharedptr.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/mutexweakptr.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/owningptr.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/setupcore.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/sharedptr.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/system.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/thread.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/threadfunc_v0.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/threadfunc_v1.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/threadfunc_v2.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/timer.h
/usr/include/ClanLib-1.0/ClanLib/Core/System/weakptr.h