About to add a way to restrict the exported namespace in cpu(1),
discovered it has been implemented already, so I documented it.

Reference: /n/sources/patch/applied/cpu-manpage
Date: Wed Nov  3 18:05:50 CET 2004

--- /sys/man/1/cpu	Wed Nov  3 18:05:50 2004
+++ /sys/man/1/cpu	Wed Nov  3 18:05:50 2004
@@ -13,6 +13,9 @@
 .B -a
 .I auth-method
 ] [
+.B -P
+.I patternfile
+] [
 .B -e
 .I encryption-hash-algs
 ] [
@@ -77,6 +80,14 @@
 exits.
 .PP
 The
+.B -P 
+.I patternfile
+argument specifies a file controlling how much of the local namespace
+will be exported to the remote system; this argument
+is passed directly to 
+.IR exportfs (1).
+.PP
+The
 .B -a
 command allows the user to specify the authentication mechanism used
 when connecting to the remote system.  The two possibilities for
@@ -157,7 +168,8 @@
 .B /sys/src/cmd/cpu.c
 .SH SEE ALSO
 .IR rc (1) ,
-.IR rio (1)
+.IR rio (1) ,
+.IR exportfs (1)
 .SH BUGS
 Binds and mounts done after the terminal
 .B lib/profile