diff --git a/src/standard.c b/src/standard.c
index 6abedb4..95d83e4 100644
--- a/src/standard.c
+++ b/src/standard.c
@@ -1007,7 +1007,7 @@
 
 /* converts <str> to a struct in_addr containing a network mask. It can be
  * passed in dotted form (255.255.255.0) or in CIDR form (24). It returns 1
- * if the conversion succeeds otherwise non-zero.
+ * if the conversion succeeds otherwise zero.
  */
 int str2mask(const char *str, struct in_addr *mask)
 {