15!:6 give the pointer to J array, the pointer to the actual data can be
found depending on you want a boxed address or not.

NB. =========================================================
NB. (iad) integer address - returns pointer to a J array
NB.
NB. monad:  iaAdd =. iadd clNoun
NB.
NB.   boo =. 'some data here ehhh!'
NB.   iad 'boo'
iad=: 3 : 0
ple=. 15!:6 <y         NB. pointer to local entry
pa=. memr ple,SZI,1 4  NB. ptr to array
''$pa+memr pa,0 1 4    NB. plus offset to data
)

NB. =========================================================
vad=: <@:iad  NB. boxed address

These two verbs come from odbc.ijs. They were there for at least 10 to 15
years I supposed, but never documentated in official helps.

Пнд, 18 Окт 2010, Henry Rich писал(а):
> Interesting.  I looked in jmf, and I tried
> 
> 15!:7 verb
> 
> which crashed J.
> 
> I can't see which of these tells me the address of the data for a noun. 
>   Can you help?
> 
> I can't make any sense of the description of 15!:6 so I didn't try it.
> 
> Henry Rich
> 
> On 10/18/2010 11:03 PM, bill lam wrote:
> > Try these foreigns.
> >
> > symget=: 15!:6 NB. get address of locale entry for name
> > symset=: 15!:7 NB. set name to address header
> >
> > examples are provided inside jmf script.
> >
> > Пнд, 18 Окт 2010, Henry Rich писал(а):
> >> All of a sudden I have to interface to a DLL that takes a big buffer as
> >> input and produces a big buffer as output.
> >>
> >> The input I have, in the variable xxx, but the DLL requires that I
> >> create a structure that points to the input.
> >>
> >> I would like to stuff the address of the data (which is read-only to the
> >> DLL) into the structure; but I can't get that address.  So I have to
> >> allocate a big area whose address I know, and memw the data to it.  Ecch.
> >>
> >> I would like a new foreign: one that returns the memory address of the
> >> data of a noun (or maybe a name).
> >>
> >> Henry Rich
> >> ----------------------------------------------------------------------
> >> For information about J forums see http://www.jsoftware.com/forums.htm
> >
> ----------------------------------------------------------------------
> For information about J forums see http://www.jsoftware.com/forums.htm

-- 
regards,
====================================================
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