How to check if C string is empty

Question

I\'m writing a very small program in C that needs to check if a certain string is empty. For the sake of this question, I\'ve simplified my code:

#include 

        

Answer 1

Since C-style strings are always terminated with the null character (\0), you can check whether the string is empty by writing

do {
   ...
} while (url[0] != '\0');

Alternatively, you could use the strcmp function, which is overkill but might be easier to read:

do {
   ...
} while (strcmp(url, ""));

Note that strcmp returns a nonzero value if the strings are different and 0 if they're the same, so this loop continues to loop until the string is nonempty.

Hope this helps!