Multithreading and RegisterHandlers

There was an issue reported a while ago

but it is still not adressed. RegisterHandlers() is not thread safe and isn’t called under locks for Unix…

Is there any reason why RegisterHandlers() shouldn’t be put under the scoped locks used before the invocations of the function?

Uh, yeah, that looks racy. I’d suggest guarding it in *SignalsMutex. I’d recommend filing a bug or sending a patch.