### strlen -- Determine String Length

Format

>     #include <string.h>
>     size_t strlen(const char *string);

Language Level: ANSI, POSIX, XPG4
strlen determines the length of string excluding the terminating null character.

Return Value
strlen returns the length of string.

Example
This example determines the length of the string that is passed to main.

    #include <stdio.h>
    #include <string.h>

    int main(int argc, char ** argv)
    {

      if ( argc != 2 )
        printf( "Usage: %s string\n", argv[0] );
      else
        printf( "Input string has a length of %i\n", strlen( argv[1] ));
      return 0;

      /***************************************************************
         The output should be:

         Length of string "How long is this string?" is 24.
      ***************************************************************/
    }

mblen -- Determine Length of Multibyte Character
strncat -- Concatenate Strings
strncmp -- Compare Strings
strncpy -- Copy Strings
strrev -- Reverse String
wcslen -- Calculate Length of Wide-Character String
<string.h>