Thread: Error comparing char*

Use strcmp(). Better yet, use std::string, upon which your attempted comparison will work.

You cannot compare character litterals with the == operator. You have to either use strcmp(), strncmp() or use std::string.

Err... Using strings makes things a whole lot easier in bigger programs. Unless you have specific needs or you are obligated to (by using a library to forces you to, for example) using std::string is *always* a better/easier/safer option than using an array of char or a pointer to a char.

Edit: Not to mention that using the standard functions as little as possible is quite the opposite of what you would want to do since they are most probably *a lot* better than any function you could write.

Code:

bool mystrcmp(const char* str1, const char* str2)
{
    if(strlen(str1) != strlen(str2)) return false;
    do
    {
        if(*str1 != *str2) return false;
    } while(str1++, *(++str2) != '\0');
    return true;
}

I like using built-in functions as little as possible.

What is your reasoning?

If you are aiming to learn by reinventing the wheel, then write your own strcmp function (or string class) and use it, or better yet, just switch back to using what is provided. If not...

I've also found that using strings makes things a lot harder in bigger programs. If all else fails, I'll have to though.

... you'll never be able to write bigger programs.

Originally Posted by RobotGymnast

I like using built-in functions as little as possible. I've also found that using strings makes things a lot harder in bigger programs. If all else fails, I'll have to though.

So if I compare each individual character it'll work, but not otherwise? that's weird..

It's not weird at all. What you are comparing is the pointers' address thus it will *always* return false.

But it doesn't really act as a pointer

Yes, it does. If the output function looks at what it points to, that's the output function's business.

It *is* a pointer. It does not output an address because ostream (cout) has overloaded the << operator for char*. You can use the dereference operator ( * ) to assign values.

Code:

char array[5 + 1] = { 0 };
char* ptr = array;
*ptr = 'H';
*(ptr + 1) = 'e';
*(ptr + 2) = 'l';
*(ptr + 3) = 'l';
*(ptr + 4) = 'o';