[patch] daemon.3

[Edgar Pettijohn]

The wording made it hard for me to understand at first.  The "unless" 
"non-zero" seem like double negatives.

Index: daemon.3
===================================================================
RCS file: /cvs/src/lib/libc/gen/daemon.3,v
retrieving revision 1.12
diff -u -p -u -r1.12 daemon.3
--- daemon.3    5 Jun 2013 03:39:22 -0000    1.12
+++ daemon.3    17 May 2016 23:42:25 -0000
@@ -43,16 +43,16 @@ The
 function is for programs wishing to detach themselves from the
 controlling terminal and run in the background as system daemons.
 .Pp
-Unless the argument
+If the argument
 .Fa nochdir
-is non-zero,
+is zero,
 .Fn daemon
 changes the current working directory to the root
 .Pq Pa / .
 .Pp
-Unless the argument
+If the argument
 .Fa noclose
-is non-zero,
+is zero,
 .Fn daemon
 will redirect standard input, standard output and standard error to
 .Pa /dev/null .