diff --git a/include/signal.h b/include/signal.h
index ec6e5a045d22..7abb92074f0c 100644
--- a/include/signal.h
+++ b/include/signal.h
@@ -54,30 +54,31 @@ __BEGIN_DECLS
 int	raise(int);
 #ifndef	_ANSI_SOURCE
 int	kill(__pid_t, int);
-int	sigaction(int, const struct sigaction *, struct sigaction *);
+int	sigaction(int, const struct sigaction * __restrict,
+	    struct sigaction * __restrict);
 int	sigaddset(sigset_t *, int);
 int	sigdelset(sigset_t *, int);
 int	sigemptyset(sigset_t *);
 int	sigfillset(sigset_t *);
 int	sigismember(const sigset_t *, int);
 int	sigpending(sigset_t *);
-int	sigprocmask(int, const sigset_t *, sigset_t *);
+int	sigprocmask(int, const sigset_t * __restrict, sigset_t * __restrict);
 int	sigsuspend(const sigset_t *);
 int	sigwait(const sigset_t *, int *);
 
-
 #ifdef _P1003_1B_VISIBLE
 
 __BEGIN_DECLS
 int sigqueue(__pid_t, int, const union sigval);
-int sigtimedwait(const sigset_t *, siginfo_t *, const struct timespec *);
-int sigwaitinfo(const sigset_t *, siginfo_t *);
+int sigtimedwait(const sigset_t * __restrict, siginfo_t * __restrict,
+	    const struct timespec * __restrict);
+int sigwaitinfo(const sigset_t * __restrict, siginfo_t * __restrict);
 __END_DECLS
 
 #endif
 #ifndef _POSIX_SOURCE
 int	killpg(__pid_t, int);
-int	sigaltstack(const stack_t *, stack_t *); 
+int	sigaltstack(const stack_t * __restrict, stack_t * __restrict); 
 int	sigblock(int);
 int	siginterrupt(int, int);
 int	sigpause(int);
diff --git a/lib/libc/sys/sigaction.2 b/lib/libc/sys/sigaction.2
index 197e9f37b875..e23535a937b6 100644
--- a/lib/libc/sys/sigaction.2
+++ b/lib/libc/sys/sigaction.2
@@ -57,7 +57,10 @@ struct  sigaction {
 #define	sa_sigaction	__sigaction_u.__sa_sigaction
 .Ed
 .Ft int
-.Fn sigaction "int sig" "const struct sigaction *act" "struct sigaction *oact"
+.Fo sigaction
+.Fa "int sig" "const struct sigaction * restrict act"
+.Fa "struct sigaction * restrict oact"
+.Fc
 .Sh DESCRIPTION
 The system defines a set of signals that may be delivered to a process.
 Signal delivery resembles the occurrence of a hardware interrupt:
diff --git a/lib/libc/sys/sigaltstack.2 b/lib/libc/sys/sigaltstack.2
index b5605d73a26d..b44db94cf115 100644
--- a/lib/libc/sys/sigaltstack.2
+++ b/lib/libc/sys/sigaltstack.2
@@ -50,7 +50,7 @@ typedef struct sigaltstack {
 } stack_t;
 .Ed
 .Ft int
-.Fn sigaltstack "const stack_t *ss" "stack_t *oss"
+.Fn sigaltstack "const stack_t * restrict ss" "stack_t * restrict oss"
 .Sh DESCRIPTION
 .Fn Sigaltstack
 allows users to define an alternate stack on which signals
diff --git a/lib/libc/sys/sigprocmask.2 b/lib/libc/sys/sigprocmask.2
index 62b3e453251b..6cb7e4955f36 100644
--- a/lib/libc/sys/sigprocmask.2
+++ b/lib/libc/sys/sigprocmask.2
@@ -43,7 +43,9 @@
 .Sh SYNOPSIS
 .In signal.h
 .Ft int
-.Fn sigprocmask "int how" "const sigset_t *set" "sigset_t *oset"
+.Fo sigprocmask
+.Fa "int how" "const sigset_t * restrict set" "sigset_t * restrict oset"
+.Fc
 .Sh DESCRIPTION
 The
 .Fn sigprocmask
diff --git a/lib/libc/sys/sigwait.2 b/lib/libc/sys/sigwait.2
index 76376a6d3131..e20595eaa94f 100644
--- a/lib/libc/sys/sigwait.2
+++ b/lib/libc/sys/sigwait.2
@@ -37,7 +37,7 @@
 .Sh SYNOPSIS
 .In signal.h
 .Ft int
-.Fn sigwait "const sigset_t *set" "int *sig"
+.Fn sigwait "const sigset_t * restrict set" "int * restrict sig"
 .Sh DESCRIPTION
 The
 .Fn sigwait
diff --git a/lib/libc_r/man/sigwait.3 b/lib/libc_r/man/sigwait.3
index 76376a6d3131..e20595eaa94f 100644
--- a/lib/libc_r/man/sigwait.3
+++ b/lib/libc_r/man/sigwait.3
@@ -37,7 +37,7 @@
 .Sh SYNOPSIS
 .In signal.h
 .Ft int
-.Fn sigwait "const sigset_t *set" "int *sig"
+.Fn sigwait "const sigset_t * restrict set" "int * restrict sig"
 .Sh DESCRIPTION
 The
 .Fn sigwait
diff --git a/lib/libc_r/uthread/uthread_sigwait.c b/lib/libc_r/uthread/uthread_sigwait.c
index a3da75fbfde7..c245e5da6ebb 100644
--- a/lib/libc_r/uthread/uthread_sigwait.c
+++ b/lib/libc_r/uthread/uthread_sigwait.c
@@ -41,7 +41,7 @@
 __weak_reference(_sigwait, sigwait);
 
 int
-_sigwait(const sigset_t *set, int *sig)
+_sigwait(const sigset_t * __restrict set, int * __restrict sig)
 {
 	struct pthread	*curthread = _get_curthread();
 	int		ret = 0;
diff --git a/lib/libkse/thread/thr_sigwait.c b/lib/libkse/thread/thr_sigwait.c
index 3cc9ff0385a5..5364d665ba85 100644
--- a/lib/libkse/thread/thr_sigwait.c
+++ b/lib/libkse/thread/thr_sigwait.c
@@ -42,7 +42,7 @@
 __weak_reference(_sigwait, sigwait);
 
 int
-_sigwait(const sigset_t *set, int *sig)
+_sigwait(const sigset_t * __restrict set, int * __restrict sig)
 {
 
 	/*
diff --git a/lib/libpthread/man/sigwait.3 b/lib/libpthread/man/sigwait.3
index 24c229718b58..6a2e05ee02cd 100644
--- a/lib/libpthread/man/sigwait.3
+++ b/lib/libpthread/man/sigwait.3
@@ -37,7 +37,7 @@
 .Sh SYNOPSIS
 .In signal.h
 .Ft int
-.Fn sigwait "const sigset_t *set" "int *sig"
+.Fn sigwait "const sigset_t * restrict set" "int * restrict sig"
 .Sh DESCRIPTION
 The
 .Fn sigwait
diff --git a/lib/libpthread/thread/thr_sigwait.c b/lib/libpthread/thread/thr_sigwait.c
index 3cc9ff0385a5..5364d665ba85 100644
--- a/lib/libpthread/thread/thr_sigwait.c
+++ b/lib/libpthread/thread/thr_sigwait.c
@@ -42,7 +42,7 @@
 __weak_reference(_sigwait, sigwait);
 
 int
-_sigwait(const sigset_t *set, int *sig)
+_sigwait(const sigset_t * __restrict set, int * __restrict sig)
 {
 
 	/*