Fix race condition in stopping FSEvent runner #40
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
The race condition is the following. When a FSEvent#stop is called, it
kills the child process and closes the pipe. It can happen that the kill
signal is sent and then succesfully the pipe is closed, before the child
process dies and the pipe in the parent is closed.
This means that IO::select() can raise a Errno::EBADF if the file
descriptor is closed while waiting in select(). This additional rescue
makes sure we shutdown in this case just like any others. This is a much
more reliable solution than adding for example a sleep() between
Process.kill and @pipe.close in FSEvent#stop.
Found because of rubinius/rubinius#2102.