extern int xread (int sock, void *buf, size_t len)
__attribute__((__warn_unused_result__));
+extern int add_string_nodup (char ***argv, int *size, int *alloc, char *str);
extern int add_string (char ***argv, int *size, int *alloc, const char *str);
extern size_t count_strings (char *const *argv);
extern void sort_strings (char **argv, int len);