From: ao950 AT FreeNet DOT Carleton DOT CA (Paul Derbyshire)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: __djgpp_base_address
Date: 14 Mar 1997 09:04:04 GMT
Organization: The National Capital FreeNet
Lines: 35
Message-ID: <5gb4a4$got@freenet-news.carleton.ca>
References: <199703051831 DOT MAA141402 AT audumla DOT students DOT wisc DOT edu> <332200de DOT SANDMANN AT clio DOT rice DOT edu> <5g0ao0$sjl AT freenet-news DOT carleton DOT ca> <3325c197 DOT 1560353 AT news DOT demon DOT co DOT uk>
Reply-To: ao950 AT FreeNet DOT Carleton DOT CA (Paul Derbyshire)
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To: djgpp AT delorie DOT com
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Alaric B. Williams (alaric AT abwillms DOT demon DOT co DOT uk) writes:
> On 10 Mar 1997 06:46:24 GMT, ao950 AT FreeNet DOT Carleton DOT CA (Paul
> Derbyshire) wrote:
> 
>>Two questions:
> 
>>* This seems to say that something like this won't work:
> 
>>  char *the_ptr;
>>  the_ptr=malloc(the_size);
>>  _go32_lock_data_memory(the_ptr,size); (syntax? not sure)
> 
>>  because later the data may find itself moved somewhere (despite being
>>  locked?) while the locked memory stays put?
> 
> No. The addresses of things can't change behind the scenes - a
> restriction of the C language due to pointer casting problems - so
> once you lock something, it's locked; you lock the *virtual* address
> range, not the physical address, which is subject to change. Anyway,
> the above code /is/ wrong - you must lock the pointer AND what it
> points to!

Oops, I know this, I forgot since I was typing a usenet posting and not
writing real useful code. :)

  char *the_ptr;
  the_ptr=malloc(the_size);
  _go32_lock_data_memory(the_ptr,size); (syntax? not sure)
  _go32_lock_data_memory(&the_ptr,sizeof(char *));
--
    .*.  Where feelings are concerned, answers are rarely simple [GeneDeWeese]
 -()  <  When I go to the theater, I always go straight to the "bag and mix"
    `*'  bulk candy section...because variety is the spice of life... [me]
Paul Derbyshire ao950 AT freenet DOT carleton DOT ca, http://chat.carleton.ca/~pderbysh