How to get the length of an array of C pointers?

Question

Possible duplicate:
array length in function argument

Is there any method like Java maybe .length from an array of C points? Thanks.

Answer 1

No, with the C pointer, you cannot determine the length in an agnostic platform.

For a real C array, though see dirkgently answer

Answer 2

You can get it with a macro:

#define sizeofa(array) sizeof array / sizeof array[ 0 ] 

if and only if the array is automatic and you access it within your definition as:

 #include <stdio.h> int main() { int x[] = { 1, 2, 3 }; printf("%zd\n", sizeofa( x )); return 0; } 

However, if you only have a (decomposed) pointer, you cannot get the length of the array without resorting to some kind of intolerable hacking implementation.

Answer 3

If you are using MSVC / MinGW, for a real C pointer, there is a NON-PORT solution:

 #include <malloc.h> char *s=malloc(1234); #ifdef __int64 printf( "%lu\n", _msize(s)); #else #endif 

For a real C array like

 AnyType myarray[] = {...}; 

or

 AnyType myarray[constVal]; 

see another answer.