Fix a race condition in the example, and add a linearized version to make it more clear what's going on. Test: none Change-Id: Id9158e4fd407b676ef364e7076985de3ad477457
File descriptors are POSIX, not C. Test: none Change-Id: Idc3c32c60f9c61e8e68aabbc4589a6c68e156e4b
Test: none Change-Id: I7dabd8f5420c757b6504254a6414da8e877d475e