src/common.h: Add some documentation for "strtoderive".

diff --git a/src/common.h b/src/common.h
index c0bea36..229f709 100644 (file)
--- a/src/common.h
+++ b/src/common.h
@@ -291,6 +291,8 @@ counter_t counter_diff (counter_t old_value, counter_t new_value);
  * (in the range [1-65535]). Returns less than zero on error. */
 int service_name_to_port_number (const char *service_name);
 
+/** Parse a string to a derive_t value. Returns zero on success or non-zero on
+ * failure. If failure is returned, ret_value is not touched. */
 int strtoderive (const char *string, derive_t *ret_value);
 
 #endif /* COMMON_H */