c - Determining the Length of a String Literal

Question

Given an array of pointers to string literals:

char *textMessages[] = {
    "Small text message",
    "Slightly larger text message",
    "A really large text message that "
    "is spread over multiple lines"
}

How does one determine the length of a particular string literal - say the third one? I have tried using the sizeof command as follows:

int size = sizeof(textMessages[2]);

But the result seems to be the number of pointers in the array, rather than the length of the string literal.

Answer 1

If you want the number computed at compile time (as opposed to at runtime with strlen) it is perfectly okay to use an expression like

sizeof "A really large text message that "
       "is spread over multiple lines";

You might want to use a macro to avoid repeating the long literal, though:

#define LONGLITERAL "A really large text message that " 
                    "is spread over multiple lines"

Note that the value returned by sizeof includes the terminating NUL, so is one more than strlen.