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Path: utzoo!mnetor!seismo!brl-adm!adm!Peter Steele - Acadia\@
From: Peter@adm.UUCP
Newsgroups: comp.lang.c
Subject: Casting NULL?
Message-ID: <3179@brl-adm.ARPA>
Date: Thu, 22-Jan-87 19:37:38 EST
Article-I.D.: brl-adm.3179
Posted: Thu Jan 22 19:37:38 1987
Date-Received: Fri, 23-Jan-87 21:07:43 EST
Sender: news@brl-adm.ARPA
Lines: 30

Its me again, although not about my infamous reviewer.

I have a question about pointers: I just recently read
a C text where whenever NULL was passed as a parameter
it was casted to the proper type. For example, if he had

void test(pc,pi)
char *pc;
int *pi;
{
  ...
}

he would call it as

test( (char *)NULL, (char *)NULL );

if the parameters were to be passed as NULL. He claimed that
this is required because pointers to different types of objects
may not be the same size. I can appreciate this but how common
is it really? Are there any byte architectures out there where
a pointer to one type of object is a different size than a pointer
to another type of object? I know that under MS-DOS, some compilers
support so-called "far" declarations, but that's not really the
same. Would anyone care to respond?

Try sending to me directly to Peter@Acadia.BITNET. If that doesn't
work, just post it over info-c.

Peter Steele