GL_APPLE_sync
https://www.khronos.org/registry/OpenGL/extensions/APPLE/APPLE_sync.txt
GL_APPLE_sync

	GL_TIMEOUT_IGNORED_APPLE 0xFFFFFFFFFFFFFFFFull
	GL_SYNC_FLUSH_COMMANDS_BIT_APPLE 0x00000001
	GL_SYNC_OBJECT_APPLE 0x8A53
	GL_MAX_SERVER_WAIT_TIMEOUT_APPLE 0x9111
	GL_OBJECT_TYPE_APPLE 0x9112
	GL_SYNC_CONDITION_APPLE 0x9113
	GL_SYNC_STATUS_APPLE 0x9114
	GL_SYNC_FLAGS_APPLE 0x9115
	GL_SYNC_FENCE_APPLE 0x9116
	GL_SYNC_GPU_COMMANDS_COMPLETE_APPLE 0x9117
	GL_UNSIGNALED_APPLE 0x9118
	GL_SIGNALED_APPLE 0x9119
	GL_ALREADY_SIGNALED_APPLE 0x911A
	GL_TIMEOUT_EXPIRED_APPLE 0x911B
	GL_CONDITION_SATISFIED_APPLE 0x911C
	GL_WAIT_FAILED_APPLE 0x911D
	GLenum glClientWaitSyncAPPLE (GLsync GLsync, GLbitfield flags, GLuint64 timeout)
	void glDeleteSyncAPPLE (GLsync GLsync)
	GLsync glFenceSyncAPPLE (GLenum condition, GLbitfield flags)
	void glGetInteger64vAPPLE (GLenum pname, GLint64* params)
	void glGetSyncivAPPLE (GLsync GLsync, GLenum pname, GLsizei bufSize, GLsizei* length, GLint *values)
	GLboolean glIsSyncAPPLE (GLsync GLsync)
	void glWaitSyncAPPLE (GLsync GLsync, GLbitfield flags, GLuint64 timeout)