diff --git a/man3/strdup.3 b/man3/strdup.3
index 49e94dcd9..59adc250b 100644
--- a/man3/strdup.3
+++ b/man3/strdup.3
@@ -120,6 +120,23 @@ set to indicate the cause of the error.
 .TP
 .B ENOMEM
 Insufficient memory available to allocate duplicate string.
+.SH ATTRIBUTES
+For an explanation of the terms used in this section, see
+.BR attributes (7).
+.TS
+allbox;
+lbw31 lb lb
+l l l.
+Interface	Attribute	Value
+T{
+.BR strdup (),
+.BR strndup (),
+.BR strdupa (),
+.br
+.BR strndupa ()
+T}	Thread safety	MT-Safe
+.TE
+
 .SH CONFORMING TO
 .\" 4.3BSD-Reno, not (first) 4.3BSD.
 .BR strdup ()