Various fixes.

	B - fixed usage, DISPLAY :0 vs :0.0
	9term - fixed various terminal things
	rc - notice traps in Read
	_p9dir - only run disk code for disks
	dirread - getdirentries on FreeBSD and Linux
		are different w.r.t. meaning of off.
	notify - set up so signals interrupt system calls
	bprint - use bfmt.
diff --git a/src/libbio/bcat.c b/src/libbio/bcat.c
index dea346a..7c9b39e 100644
--- a/src/libbio/bcat.c
+++ b/src/libbio/bcat.c
@@ -22,8 +22,12 @@
 {
 	int i;
 	Biobuf b, *bp;
+	Fmt fmt;
 
 	Binit(&bout, 1, O_WRONLY);
+	Bfmtinit(&fmt, &bout);
+	fmtprint(&fmt, "hello, world\n");
+	Bfmtflush(&fmt);
 
 	if(argc == 1){
 		Binit(&b, 0, O_RDONLY);