Re: "Mastering C Pointers"....

From: Keith Thompson (kst_at_cts.com)
Date: 11/05/03 

Date: Wed, 05 Nov 2003 21:36:29 GMT

Sheldon Simms <sheldonsimms@yahoo.com> writes:
[...]
> A null pointer constant is not a pointer at all. It first becomes a
> (null) pointer after conversion to a pointer type.

A null pointer constant is a syntactic entity, a construct in C source
code. A null pointer is a value that can exist at run time. They
have much the same relationship as an identifier and an object, or the
consecutive characters '4' and '2' in your foo.c file and the bits
representing the integer 42 in your running program. 

-- 
Keith Thompson (The_Other_Keith) kst@cts.com  <http://www.ghoti.net/~kst>
San Diego Supercomputer Center           <*>  <http://www.sdsc.edu/~kst>
Schroedinger does Shakespeare: "To be *and* not to be"

Relevant Pages

  • Re: 0, NULL and variadic functions
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  • Re: NULL with representation other then all bits 0
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  • Re: NULL with representation other then all bits 0
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    (comp.lang.c)
  • Re: does a program work in all cases?
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    (comp.lang.c)
  • Re: Null pointers
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    (comp.lang.c)