Re: (n-for-each-par-map 16 store download (reverse (iota (max-id))))) crash

[Mark H Weaver <mhw@netris.org>]

Hi,

Amirouche Boubekki <amirouche@hypermove.net> writes:

> On 2018-07-05 20:30, Mark H Weaver wrote:
>> Amirouche Boubekki <amirouche@hypermove.net> writes:
>>
>>> (define (store pair)
>>>   (if (null? pair)
>>>       (format #t "X\n")
>>>       (let ((port (open-file "hn.scm" "a")))
>>>         (format #t "~a\n" (car pair))
>>
>> These calls to (format #t ...), which write to a port that is shared by
>> multiple threads, should be performed while holding a mutex to prevent
>> concurrent writes to the same port.
>
> Ok, but it's called by:
>
>   (n-for-each-par-map n sproc pproc lst1 lst2)
>
> and the manual says about SPROC that :
>
>   The sproc calls are made serially,
>   in list element order, one at a time.
>
> In my case SPROC is 'store', so my understanding is that
> it should require no lock.

You're right, my mistake.  I'm not sure what's going on here.  It would
be good to send a message to bug-guile@gnu.org to file a bug report, and
to continue the discussion there.

    Thanks!
      Mark