Rename kernel-only members of semid_ds and msgid_ds.

This deliberately breaks the API in preperation for future syscall
revisions which will remove these nonstandard members.

In an exp-run a single port (devel/qemu-user-static) was found to
use them which it did becuase it emulates system calls.  This has
been fixed in the ports tree.

PR:		224443 (exp-run)
Reviewed by:	kib, jhb (previous version)
Exp-run by:	antoine
Sponsored by:	DARPA, AFRP
Differential Revision:	https://reviews.freebsd.org/D14490

2 files changed, 3 insertions, 3 deletions

diff --git a/lib/libc/sys/msgctl.2 b/lib/libc/sys/msgctl.2
index 34c52633d8c8..1ca61ed77b2a 100644
--- a/lib/libc/sys/msgctl.2
+++ b/lib/libc/sys/msgctl.2
@@ -63,8 +63,8 @@ and contains (amongst others) the following members:
 .Bd -literal
 struct msqid_ds {
 	struct	ipc_perm msg_perm;	/* msg queue permission bits */
-	struct	msg *msg_first;	/* first message in the queue */
-	struct	msg *msg_last;	/* last message in the queue */
+	struct	msg *__msg_first;	/* kernel data, don't use */
+	struct	msg *__msg_last;	/* kernel data, don't use */
 	msglen_t msg_cbytes;	/* number of bytes in use on the queue */
 	msgqnum_t msg_qnum;	/* number of msgs in the queue */
 	msglen_t msg_qbytes;	/* max # of bytes on the queue */
diff --git a/lib/libc/sys/semctl.2 b/lib/libc/sys/semctl.2
index adfb9ef52d79..0f76c282f211 100644
--- a/lib/libc/sys/semctl.2
+++ b/lib/libc/sys/semctl.2
@@ -145,7 +145,7 @@ is defined as follows:
 .Bd -literal
 struct semid_ds {
         struct  ipc_perm sem_perm;      /* operation permission struct */
-        struct  sem *sem_base;  /* pointer to first semaphore in set */
+        struct  sem *__sem_base;  /* kernel data, don't use */
         u_short sem_nsems;      /* number of sems in set */
         time_t  sem_otime;      /* last operation time */
         time_t  sem_ctime;      /* last change time */