import the plan 9 libraries libc (lib9) and libbio into the tree.
remove the dependency on /home/r.

SVN=122482
diff --git a/src/libbio/bbuffered.c b/src/libbio/bbuffered.c
new file mode 100644
index 0000000..2ddb29b
--- /dev/null
+++ b/src/libbio/bbuffered.c
@@ -0,0 +1,46 @@
+/*
+http://code.google.com/p/inferno-os/source/browse/libbio/bbuffered.c
+
+	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
+	Revisions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com).  All rights reserved.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#include	<u.h>
+#include	<libc.h>
+#include	<bio.h>
+
+int
+Bbuffered(Biobuf *bp)
+{
+	switch(bp->state) {
+	case Bracteof:
+	case Bractive:
+		return -bp->icount;
+
+	case Bwactive:
+		return bp->bsize + bp->ocount;
+
+	case Binactive:
+		return 0;
+	}
+	fprint(2, "Bbuffered: unknown state %d\n", bp->state);
+	return 0;
+}