This enables us to properly grab the @sigchld_mutex and synchronize
with writers.
It turns out that signal handlers execute on the main thread and may
interleave with other writers. This manifested as handle_sigchldwriteing to pipes that had already been closed (by the IO.pipe)
block, resulting in nasty exceptions.
By grabbing the lock, we ensure that we serialize reading the list of
wakeup pipes properly with respect to writers.
andrew-stripe
commented
7 years ago
This enables us to properly grab the
@sigchld_mutexand synchronize with writers.It turns out that signal handlers execute on the main thread and may interleave with other writers. This manifested as
handle_sigchldwriteing to pipes that had already been closed (by theIO.pipe) block, resulting in nasty exceptions.By grabbing the lock, we ensure that we serialize reading the list of wakeup pipes properly with respect to writers.
r? @andrew-stripe