Reintroduce the snp(4) driver.

Because the TTY hooks interface was not finished when I imported the
MPSAFE TTY layer, I had to disconnect the snp(4) driver. This snp(4)
implementation has been sitting in my P4 branch for some time now.
Unfortunately it still doesn't use the same error handling as snp(4)
(returning codes through FIONREAD), but it should already be usable.

I'm committing this to SVN, hoping someone else could polish off its
rough edges. It's always better than having a broken driver sitting in
the tree.

1 files changed, 19 insertions, 7 deletions

diff --git a/share/man/man4/snp.4 b/share/man/man4/snp.4
index 76bcc53..2545164 100644
--- a/share/man/man4/snp.4
+++ b/share/man/man4/snp.4
@@ -1,7 +1,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd September 18, 2005
+.Dd November 5, 2008
 .Dt SNP 4
 .Os
 .Sh NAME
@@ -77,11 +77,23 @@ The
 .Nm
 device first appeared in
 .Fx 2.1 .
+In
+.Fx 8.0
+the
+.Nm
+driver was rewritten to work with the replaced TTY subsystem.
 .Sh AUTHORS
-.An Ugen J.S. Antsilevich Aq ugen@NetVision.net.il
+The author of the current implementation is
+.An Ed Schouten Aq ed@FreeBSD.org .
+Previous versions of
+.Nm
+were based on code written by
+.An Ugen J.S. Antsilevich Aq ugen@NetVision.net.il .
 .Sh BUGS
-Caveat emptor!
-This manual page is horribly stale and wildly inaccurate in some places.
-.Pp
-While in line mode, user input cannot be seen.
-No signals may be sent to the observed tty.
+This version of
+.Nm
+does not return proper error codes when calling
+.Dv FIONREAD .
+It also does not allow
+.Dv SNPSTTY
+to detach itself from the TTY.