empty fields.
Caveat: It modifies the original string.
+ Caveat: These functions cannot be used on constant strings.
+ Caveat: The identity of the delimiting character is lost.
Caveat: It doesn't work with multibyte strings unless all of the delimiter
- characters are ASCII characters < 0x30. */
+ characters are ASCII characters < 0x30.
+
+ See also strtok_r(). */
extern char *strsep (char **stringp, const char *delim);