exportfs, oexportfs, iostats: make -d log to stderr

exportfs -d logs 9p traffic to /tmp/exportdb.
-f allows writing to a different file.
exportfs silently continues if it doesn't have
permissions to create or write to /tmp/exportdb.
These are poor behaviors.

A better default is to write to stderr, since it
is 9P debug info that is better immediately printed,
and not user info that is better handled by syslog().
As a result, -f is obsolete and thus removed.
Redirect responsibility is now on rc.
As a side effect, rc will fail if it doesn't
have permissions to write.

exportfs(4) is updated to reflect all changes
and with a better Synopsis.

oexportfs is changed to match exportfs.
oexportfs(4) is updated to reflect all changes.
The Synopsis is not changed due to the number of flags.

Removed -f from iostats.
iostats(4) is updated to reflect all changes.
---

1 files changed, 2 insertions, 5 deletions

diff --git a/sys/man/4/oexportfs b/sys/man/4/oexportfs
index 180ad204f..64f156c09 100644
--- a/sys/man/4/oexportfs
+++ b/sys/man/4/oexportfs
@@ -26,11 +26,8 @@ services.
 .PP
 The options are:
 .TP
-.B -d -f \fIdbgfile
-Log all 9P traffic to
-.I dbgfile
-(default
-.BR /tmp/exportdb ).
+.B -d
+Log all 9P traffic to standard error.
 .TP
 .B -P \fIpatternfile
 Restrict the set of exported files.