Index: lib/libc/net/Makefile.inc
===================================================================
--- lib/libc/net/Makefile.inc
+++ lib/libc/net/Makefile.inc
@@ -61,7 +61,9 @@
 MLINKS+=gethostbyname.3 endhostent.3 gethostbyname.3 gethostbyaddr.3 \
 	gethostbyname.3 gethostbyname2.3 gethostbyname.3 gethostent.3 \
 	gethostbyname.3 herror.3 gethostbyname.3 hstrerror.3 \
-	gethostbyname.3 sethostent.3
+	gethostbyname.3 sethostent.3 \
+	gethostbyname.3 gethostbyname_r.3 gethostbyname.3 gethostbyname2_r.3 \
+	gethostbyname.3 gethostbyaddr_r.3
 MLINKS+=getifaddrs.3 freeifaddrs.3
 MLINKS+=getifmaddrs.3 freeifmaddrs.3
 MLINKS+=getipnodebyname.3 getipnodebyaddr.3 getipnodebyname.3 freehostent.3
Index: lib/libc/net/gethostbyname.3
===================================================================
--- lib/libc/net/gethostbyname.3
+++ lib/libc/net/gethostbyname.3
@@ -39,7 +39,10 @@
 .Nm sethostent ,
 .Nm endhostent ,
 .Nm herror ,
-.Nm hstrerror
+.Nm hstrerror ,
+.Nm gethostbyname_r ,
+.Nm gethostbyname2_r ,
+.Nm gethostbyaddr_r
 .Nd get network host entry
 .Sh LIBRARY
 .Lb libc
@@ -62,6 +65,12 @@
 .Fn herror "const char *string"
 .Ft const char *
 .Fn hstrerror "int err"
+.Ft int
+.Fn gethostbyname_r "const char *name" "struct hostent *he" "char *buffer" "size_t buflen" "struct hostent **result" "int *h_errnop"
+.Ft int
+.Fn gethostbyname2_r "const char *name" "int af" "struct hostent *he" "char *buffer" "size_t buflen" "struct hostent **result" "int *h_errnop"
+.Ft int
+.Fn gethostbyaddr_r "const void *addr" "socklen_t len" "int af" "struct hostent *hp" "char *buf" "size_t buflen" "struct hostent **result" "int *h_errno"p
 .Sh DESCRIPTION
 .Bf -symbolic
 The
@@ -227,6 +236,26 @@
 value of the
 .Fa err
 argument.
+.Pp
+Functions with the
+.Em _r
+suffix provide reentrant versions of their respective counterparts.
+The caller must supply five additional parameters: a
+.Vt struct hostent
+variable to be filled on success, a
+.Va buffer
+of
+.Va buflen
+bytes in size, a
+.Vt struct hostent
+.Va result
+variable that will point to the result on success or be set to
+.Dv NULL
+on failure or if the name is not found.
+The
+.Va h_errnop
+variable will be filled with the error code if any.
+All these functions return 0 on success.
 .Sh FILES
 .Bl -tag -width /etc/nsswitch.conf -compact
 .It Pa /etc/hosts