diff --git a/lib/libc/sys/sendfile.2 b/lib/libc/sys/sendfile.2
index 275c047ea93e..8c7dadbda7e1 100644
--- a/lib/libc/sys/sendfile.2
+++ b/lib/libc/sys/sendfile.2
@@ -61,7 +61,9 @@ argument specifies how many bytes of the file should be sent, with 0 having the
 meaning of send until the end of file has been reached.
 .Pp
 An optional header and/or trailer can be sent before and after the file data by specifying
-a pointer to a struct sf_hdtr, which has the following structure:
+a pointer to a
+.Vt "struct sf_hdtr" ,
+which has the following structure:
 .Pp
 .Bd -literal -offset indent -compact
 struct sf_hdtr {
@@ -76,7 +78,9 @@ The
 .Fa headers
 and
 .Fa trailers
-pointers, if non-NULL, point to arrays of struct iovec structures.
+pointers, if
+.Pf non- Dv NULL ,
+point to arrays of struct iovec structures.
 See the
 .Fn writev
 system call for information on the iovec structure.
@@ -86,7 +90,9 @@ arrays is specified by
 and
 .Fa trl_cnt .
 .Pp
-If non-NULL, the system will write the total number of bytes sent on the socket to the
+If
+.Pf non- Dv NULL ,
+the system will write the total number of bytes sent on the socket to the
 variable pointed to by
 .Fa sbytes .
 .Pp