diff --git a/man3/atoi.3 b/man3/atoi.3
index c5894d325..3c6527a5b 100644
--- a/man3/atoi.3
+++ b/man3/atoi.3
@@ -81,7 +81,18 @@ functions behave the same as
 except that they convert the initial portion of the
 string to their return type of \fIlong\fP or \fIlong long\fP.
 .SH RETURN VALUE
-The converted value.
+The converted value or 0 on error.
+.SH BUGS
+.I errno
+is not set on error so there is no way to distinguish between 0 as an
+error and as the converted value.
+No checks for overflow or underflow are done.
+Only input in decimal base can be converted.
+It's recommended to use
+.BR strtol ()
+and
+.BR strtoul ()
+family of functions in new programs.
 .SH ATTRIBUTES
 For an explanation of the terms used in this section, see
 .BR attributes (7).