Function in C

[AndrewAPrice]

The advantages of floating point addresses, you could check to see if it's a NaN

[Solar]

that's why you should compare to NULL instead of comparing to 0. On machines without MMU you'll see often enough that RAM starts at 0 and the program is in ROM somewhere else. And then your code must still be able to work.

Ehm... actually, no.

The definition of a null pointer constant is "an integer constant expression with the value 0, or such an expression cast to type void *".

[Creature]

that's why you should compare to NULL instead of comparing to 0. On machines without MMU you'll see often enough that RAM starts at 0 and the program is in ROM somewhere else. And then your code must still be able to work.

Ehm... actually, no.

The definition of a null pointer constant is "an integer constant expression with the value 0, or such an expression cast to type void *".

Yep, I believe in C, NULL is defined as

Code: Select all

#define NULL ((void *) 0) //or something equivalent.

whilst in C++ it's defined as (or should be defined as, if you use it, according to Bjarne Stroustrup):

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#define NULL 0