Question

For example:

This is what I tried:

#include "stdafx.h"
#include <ctype.h>

char *mystrcat(char *s1p, char *s2p); 
char main(void)
{
    ...........................
}

char *mystrcat(char *s1p, char *s2p) 
{

    printf("whatever = %s%s\n", s1p, s2p);
    return 0;   
}

How do I make this work with the 3rd pointer and have it store p1 and p2?

Answer 1

Replace: *mystrcat(string1, string2);
With: char *string3 = mystrcat(string1, string2);

Also if your teacher wants char*’s instead of

char string1[80];  
char string2[80];

You could do

char *string1 = malloc(80*sizeof(char));
char *string2 = malloc(80*sizeof(char));

To concat your strings:

char *mystrcat(char *s1p,char *s2p) {
    char *cat = malloc(2*80*sizeof(char));
    int i = 0;
    while(s1p[i]!='\o') {
        cat[i] = s1p[i];
        i++;
    }
    int j = 0;
    while(s2p[j]!='\o') {
        cat[i+j] = s2p[j];
        j++;
    }
    return cat;   
}