size_t
The size_t type is defined in stdio.h, stddef.h, stdlib.h, and string.h. This type is used for defining the sizes of strings and memory blocks. It is defined as:
typedef unsigned int size_t;
and is used as shown in the following example:
#include <string.h>
void lfunc (char *string) {
size_t string_length;
string_length = strlen(string);
}