diff --git a/lib/libsys/getrlimit.2 b/lib/libsys/getrlimit.2
--- a/lib/libsys/getrlimit.2
+++ b/lib/libsys/getrlimit.2
@@ -112,6 +112,9 @@
 Please see
 .Xr tuning 7
 for a complete description of this sysctl.
+.It Dv RLIMIT_UMTXP
+The limit of the number of process-shared posix thread library objects
+allocated by user id.
 .It Dv RLIMIT_VMEM
 An alias for
 .Dv RLIMIT_AS .