Problem in understanding few things related to FUNCTION RETURNING POINTER
I am referring a book programming in c by Kochan and i am not getting few things on a particular code.
Code:
#include <stdio.h>
struct entry
{
int value;
struct entry *next;
};
struct entry *findEntry (struct entry *listPtr, int match)
{
while ( listPtr != (struct entry *) 0 )
if ( listPtr->value == match )
return (listPtr);
else
listPtr = listPtr->next;
return (struct entry *) 0;
}
int main (void)
{
struct entry *findEntry (struct entry *listPtr, int match);
struct entry n1, n2, n3;
struct entry *listPtr, *listStart = &n1;
int search;
n1.value = 100;
n1.next = &n2;
n2.value = 200;
n2.next = &n3;
n3.value = 300;
n3.next = 0;
printf ("Enter value to locate: ");
scanf ("%i", &search);
listPtr = findEntry (listStart, search);
if ( listPtr != (struct entry *) 0 )
printf ("Found %i.\n", listPtr->value);
else
printf ("Not found.\n");
return 0;
}
First thing is the (struct entry *) 0 expression in while loop and other one is return (struct entry *) 0;
Also does the struct entry *findEntry and struct entry * findEntry(with space asterik and function name) makes any difference
