Looks like either need to fix J engine or the documentation.

On Sat, 26 Feb 2022 at 4:13 AM Raul Miller <[email protected]> wrote:

> I am trying to understand what you mean here.
>
> Your 'read' verb does not read from memory. Instead, it writes a zero
> to an offset in some freshly allocated memory and returns the address
> of that allocation.
>
> Similarly, your 'write' verb does not write to memory. Instead, it
> reads characters from the previously allocated memory, up to the point
> where it finds a zero (and fortunately, you had ensured that there
> would be one when you invoked 'read').
>
> Anyways, basically it looks like you've built a small system to read
> some arbitrary bytes from memory and then are using them in some
> larger algorithm.
>
> But I am not sure why you would expect an operation which reads
> arbitrary memory to be deterministic.
>
> Have I overlooked something important?
>
> Thanks,
>
> --
> Raul
>
> On Fri, Feb 25, 2022 at 3:01 PM John Ference <[email protected]>
> wrote:
> >
> > Hello,
> > Is this construction consistent with the design specs of the memory
> > management functions?
> >
> > s =. 'Hello world'
> >
> > read =. {{p [ y memw p,0,(>: # y),2 [ p =. mema >: # y}}
> >
> > write =. {{res [ memf y [ res =. memr y,0,_1,2}}
> >
> >
> > NB. test:
> >
> > <./ (,. write@read&.> <\ s) = (,. <\ s)
> >
> > Results are non-deterministic, but the results at the test at the end
> > typically return 0.
> >
> > Visual inspection of the result suggests the capability to auto-append
> and
> > then auto-find an end-of-string indicator may not be working.
> >
> > specs: https://code.jsoftware.com/wiki/Guides/DLLs/Memory_Management
> >
> > Regards,
> > John
> > ----------------------------------------------------------------------
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