Question

How would I manually concatenate two char arrays without using the strncpy function?

Can I just say char1 + char2?

Or would I have to write a for loop to get individual elements and add them like this:

addchar[0] = char1[0];
addchar[1] = char1[1];
etc
etc
addchar[n] = char2[0];
addchar[n+1] = char2[1];
etc
etc

To clarify, if
char1 = “happy”
char2 = “birthday”

I want addchar to = happybirthday

Answer 1

If you consider two trivial loops to be “manual”, then yes, without using the standard library this is the only way.

char *append(const char *a, const char *b) {
    int i = 0;
    size_t na = strlen(a);
    size_t nb = strlen(b);
    char *r = (char*)calloc(na + nb + 1, 1);
    for (i = 0; i < na; i++) {
        r[i] = a[i];
    }
    for (i = 0; i < nb; i++) {
        r[na + i] = b[i];
    }
    return r;
}

Remember to call free.