diff --git a/lib/libc/sys/sigaction.2 b/lib/libc/sys/sigaction.2
index eb15a11b8ef2..85da04e3c3eb 100644
--- a/lib/libc/sys/sigaction.2
+++ b/lib/libc/sys/sigaction.2
@@ -287,7 +287,7 @@ is not allowed to block
 .Dv SIGKILL
 or
 .Dv SIGSTOP .
-This is done silently by the system.
+Attempting to do so will cause the call to fail.
 .Sh RETURN VALUES
 A 0 value indicated that the call succeeded.  A \-1 return value
 indicates an error occurred and