[Python-Dev] POSIX thread code

[Gerald S. Williams]

I was trying to avoid taking sides on the keyboard interrupt
issue. I do prefer only having to type ^C once, but Python
doesn't always do that now (at least not on my platforms),
and there are certainly issues trying to do it portably. I
wouldn't want to be involved in that effort.

The point of the quote was to show that Mutexes/Condition
variables have (or at least can have) the same behavior
wrt interrupts as this:
  do {
    status = sem_wait(lock);
  } while ((status == -1) && (errno == EINTR));

So we can treat keyboard interrupts as a separate issue.

-Jerry

-O Gerald S. Williams, 22Y-103GA : mailto:gsw@agere.com O-
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Tim Peters wrote:
> I'm deadly opposed to letting a keyboard interrupt break out of a wait for a
> Python lock.
[...]
> >  If a signal is delivered to a thread waiting for a mutex,
> >  upon return from the signal handler the thread shall resume
> >  waiting for the mutex as if it was not interrupted.
> > and:
> >  If a signal is delivered to a thread waiting for a condition
> >  variable, upon return from the signal handler the thread shall
> >  resume waiting for the condition variable as if it was not
> >  interrupted, or it shall return zero due to spurious wakeup.
> 
> Sorry, I don't grasp what the point of this quoting was, unless it was a
> roundabout way of merely confirming that keyboard interrupts can't break out
> of a wait for a Python lock today (which was known and said before).