Use .Dv NULL when referring to NULL C pointers, instead of "nil".

6 files changed, 32 insertions, 11 deletions

diff --git a/lib/libc/sys/acct.2 b/lib/libc/sys/acct.2
index aa071d9..1119bbe 100644
--- a/lib/libc/sys/acct.2
+++ b/lib/libc/sys/acct.2
@@ -51,7 +51,9 @@ system call enables or disables the collection of system accounting
 records.
 If the argument
 .Fa file
-is a nil pointer, accounting is disabled.
+is a
+.Dv NULL
+pointer, accounting is disabled.
 If
 .Fa file
 is an
diff --git a/lib/libc/sys/adjtime.2 b/lib/libc/sys/adjtime.2
index 373c46e..a5f873e 100644
--- a/lib/libc/sys/adjtime.2
+++ b/lib/libc/sys/adjtime.2
@@ -72,7 +72,9 @@ may not be finished when
 is called again.
 If
 .Fa olddelta
-is non-nil,
+is not a
+.Dv NULL
+pointer,
 the structure pointed to will contain, upon return, the
 number of microseconds still to be corrected
 from the earlier call.
diff --git a/lib/libc/sys/aio_suspend.2 b/lib/libc/sys/aio_suspend.2
index 06d278a..77d8ec5 100644
--- a/lib/libc/sys/aio_suspend.2
+++ b/lib/libc/sys/aio_suspend.2
@@ -56,10 +56,14 @@ NULL will be silently ignored.
 .Pp
 If
 .Fa timeout
-is a non-nil pointer, it specifies a maximum interval to suspend.
+is not a
+.Dv NULL
+pointer, it specifies a maximum interval to suspend.
 If
 .Fa timeout
-is a nil pointer, the suspend blocks indefinitely.
+is a
+.Dv NULL
+pointer, the suspend blocks indefinitely.
 To effect a
 poll, the
 .Fa timeout
diff --git a/lib/libc/sys/getitimer.2 b/lib/libc/sys/getitimer.2
index babcd3b..2efb0f8 100644
--- a/lib/libc/sys/getitimer.2
+++ b/lib/libc/sys/getitimer.2
@@ -66,7 +66,9 @@ system call sets a timer to the specified
 .Fa value
 (returning the previous value of the timer if
 .Fa ovalue
-is non-nil).
+is not a
+.Dv NULL
+pointer).
 .Pp
 A timer value is defined by the
 .Fa itimerval
diff --git a/lib/libc/sys/recv.2 b/lib/libc/sys/recv.2
index 51d8d61..8c3e1b6 100644
--- a/lib/libc/sys/recv.2
+++ b/lib/libc/sys/recv.2
@@ -63,7 +63,9 @@ it is connection-oriented.
 .Pp
 If
 .Fa from
-is non-nil, and the socket is not connection-oriented,
+is not
+.Dv NULL ,
+and the socket is not connection-oriented,
 the source address of the message is filled in.
 The
 .Fa fromlen
@@ -82,7 +84,8 @@ socket (see
 .Xr connect 2 )
 and is identical to
 .Fn recvfrom
-with a nil
+with a
+.Dv NULL
 .Fa from
 argument.
 As it is redundant, it may not be supported in future releases.
diff --git a/lib/libc/sys/select.2 b/lib/libc/sys/select.2
index bacd76e..193c903 100644
--- a/lib/libc/sys/select.2
+++ b/lib/libc/sys/select.2
@@ -108,25 +108,33 @@ to the maximum number of descriptors supported by the system.
 .Pp
 If
 .Fa timeout
-is a non-nil pointer, it specifies the maximum interval to wait for the
+is not a
+.Dv NULL
+pointer, it specifies the maximum interval to wait for the
 selection to complete.
 System activity can lengthen the interval by
 an indeterminate amount.
 .Pp
 If
 .Fa timeout
-is a nil pointer, the select blocks indefinitely.
+is a
+.Dv NULL
+pointer, the select blocks indefinitely.
 .Pp
 To effect a poll, the
 .Fa timeout
-argument should be non-nil, pointing to a zero-valued timeval structure.
+argument should not be
+.Dv NULL ,
+but it should point to a zero-valued timeval structure.
 .Pp
 Any of
 .Fa readfds ,
 .Fa writefds ,
 and
 .Fa exceptfds
-may be given as nil pointers if no descriptors are of interest.
+may be given as
+.Dv NULL
+pointers if no descriptors are of interest.
 .Sh RETURN VALUES
 The
 .Fn select