C print whole string variable (ignore \0 termination)

Question

An example says more than thousand words:

unsigned char *hello = (unsigned char*)malloc(STR_LEN * sizeof(unsigned char));
const char *str= "haha";
memcpy(hello, str, strlen(str) + 1);

How can I print the content of the whole hello-variable (printf("%s",..) would only respect the part before the \0-termination and not all STR_LEN characters).

Answer 1

You can use fwrite to write unformatted data:

char buf[4] = { 1, 2 };

fwrite(buf, 1, 4, stdout);   // writes the bytes 1, 2, 0, 0

You could use fwrite(hello, 1, STR_LEN, stdout), but note that you're not allowed to read uninitialized data (so you should use calloc instead or initialize the data in some other way).

Answer 2

You'd have to write your own for loop that goes from hello to hello+STR_LEN, and prints each character one at a time.

for (unsigned char *c = hello, e = hello +STR_LEN; c < e; ++c) {
    printf("%c", *c);
}

Answer 3

int i;
for(i = 0; i < STR_LEN; i++) {
    putchar(hello[i]);
}