diff --git a/man3/ptsname.3 b/man3/ptsname.3
index 394138b7a..0137fe741 100644
--- a/man3/ptsname.3
+++ b/man3/ptsname.3
@@ -63,12 +63,9 @@ On failure, NULL is returned.
 On success,
 .BR ptsname_r ()
 returns 0.
-On failure, a nonzero value is returned
-and
-.I errno
-is set to indicate the error.
-.\" In fact the errno value is also returned as the function
-.\" result -- MTK, Dec 04
+On failure, an error number is returned to indicate the error.
+.\" In glibc, the error number is not only returned as the return value
+.\" but also stored in errno. But this is not true for musl libc.
 .SH ERRORS
 .TP
 .B EINVAL