Re: Warning: Unstable POSIX threads support comitted to CVS

[Mikael Djurfeldt]

Marius Vollmer <address@hidden> writes:

> Mikael Djurfeldt <address@hidden> writes:
>
>> It is very irritating that signals are delivered to whatever thread
>> happens to run for the moment.
>
> Do you refer to the execution of POSIX signal handlers or to the
> execution of Scheme signal handlers?

With "delivered" I'm thinking of "end-point" delivery, that is
execution of Scheme signal handlers.  I'm thinking of channeling all
signals to a particular target thread (which becomes the one to run
its handlers until the target is switched).

> That is, signals-plus-threads are quite nasty on Linux.  I think we
> should have a dedicated signal handling thread that polls for signals
> and marks the relevant system asyncs when they arrive.

That sounds like a good solution.  Are there particular reasons why a
dedicated thread is needed rather than that an arbitrary POSIX signal
handler of an arbitrary receives the signal sets the asyncs of the
"foreground" thread?

I guess one such reason could be that we, in that case, could block
signals for all threads except the signal one, with the benefit that a
particular signal is only received "once" (rather than getting a
"barrage" of async marks at asyncronous points in time), right?

M