Re: Concurrency

[Giuseppe Scrivano]

I have changed how `make-mutex' works.  Now it accepts an optional
argument; if the argument is non nil then a recursive mutex is created,
by default it is nil.  By default a normal mutex (non recursive) is
created.

I have also changed mutex-unlock on a recursive mutex to match the
number of times it was mutex-lock'ed.  To release a recursive mutex it
must be unlocked as many times as it was locked.

I have added a mutexp function that I forgot to add before.

Giuseppe



Stefan Monnier <address@hidden> writes:

>>>>> (mutex-lock MUTEX)
>>>>> Acquire a mutex.  If already held by this thread, returns.
>>>> I.e. it's a "recursive/reentrant mutex".
>>> Hmm -- is it fully recursive, where you must unlock it as many times as
>>> you locked it?  (I don't much care for the semi-recursive kind where one
>>> unlock is sufficient regardless of the number of lock operations...)
>> No, it is sufficient only one unlock to release it.
>
> Huh?  That sounds like a bug,
>
>
>         Stefan