Re: Improving Shepherd

[Mark H Weaver]

Jelle Licht <address@hidden> writes:

> tl;dr: I cannot seem to block signals from being handled by guile in
> some way, which to me seems a prerequisite for using signalfd-based
> signal handling. My uneducated guess is that guile needs to support a
> way to set signal masks for all threads in order to deal with this.

Does POSIX provide a way to set the signal mask for another thread?
Last time I looked, I couldn't find one.

I've long desired to get rid of the signal thread in Guile, and instead
arrange for signals to be delivered directly to the thread that's
supposed to receive it.  Guile's 'sigaction' has long allowed the user
to specify which thread should receive each kind of signal, although
POSIX doesn't support this.

I want to do this for a couple of reasons.  One is to avoid spawning
threads unless the user asks for it, to avoid possible safety issues
with fork.  Another reason is that I'd like to arrange for long-running
system calls to be reliably interrupted when a signal is received.

The main thing I've been stuck on is that I haven't found a way to set
the signal mask on other threads.

      Mark