from charles, and the sources patch of the same name

Add a -s srvname option to rdbfs, allowing debugging sessions to be shared
or later reattached after disconnection.

Reference: /n/atom/patch/applied2013/rdbfs-srvname
Date: Thu Jun 13 05:08:26 CES 2013
Signed-off-by: quanstro@quanstro.net

--- /sys/src/cmd/rdbfs.c	Thu Jun 13 05:07:55 2013
+++ /sys/src/cmd/rdbfs.c	Thu Jun 13 05:07:55 2013
@@ -124,7 +124,6 @@
 	Xfpregs,
 	Xkregs,
 	Xmem,
-	Xnote,
 	Xproc,
 	Xregs,
 	Xtext,
@@ -138,12 +137,13 @@
 char*	portname = "/dev/eia0";
 char*	textfile = "/386/9pc";
 char*	procname = "1";
+char*	srvname;
 Channel* rchan;
 
 void
 usage(void)
 {
-	fprint(2, "usage: rdbfs [-p procnum] [-t textfile] [serialport]\n");
+	fprint(2, "usage: rdbfs [-p procnum] [-s srvname] [-t textfile] [serialport]\n");
 	exits("usage");
 }
 
@@ -224,11 +224,9 @@
 					goto Break2;
 				}else{
 					DBG(2, "unknown message\n");
-					break;
 				}
 			}
 		}
-		respond(r, "timed out");
 	Break2:;
 	}
 }
@@ -236,10 +234,20 @@
 void
 attachremote(char* name)
 {
+	int fd;
+	char buf[128];
+
 	print("attach %s\n", name);
 	rfd = open(name, ORDWR);
 	if(rfd < 0)
-		sysfatal("can't open remote %s: %r", name);
+		sysfatal("can't open remote %s", name);
+
+	sprint(buf, "%sctl", name);
+	fd = open(buf, OWRITE);
+	if(fd < 0)
+		sysfatal("can't set baud rate on %s", buf);
+	write(fd, "B9600", 6);
+	close(fd);
 	Binit(&rfb, rfd, OREAD);
 }
 
@@ -293,7 +301,7 @@
 		respond(r, nil);
 		break;
 	case Xstatus:
-		n = sprint(buf, "%-28s%-28s%-28s", "remote", getuser(), "Broken");
+		n = sprint(buf, "%-28s%-28s%-28s", "remote", "system", "New");
 		for(i = 0; i < 9; i++)
 			n += sprint(buf+n, "%-12d", 0);
 		readstr(r, buf);
@@ -309,15 +317,13 @@
 {
 	char buf[ERRMAX];
 
-	r->ofcall.count = r->ifcall.count;
 	switch((uintptr)r->fid->file->aux) {
 	case Xctl:
-	case Xnote:
 		if(strncmp(r->ifcall.data, "kill", 4) == 0 ||
 		   strncmp(r->ifcall.data, "exit", 4) == 0) {
-//			fprint(rfd, "%c", 0);	/* break; would reboot remote */
 			respond(r, nil);
-			threadexitsall(nil);
+			postnote(PNGROUP, getpid(), "umount");
+			exits(nil);
 		}else if(strncmp(r->ifcall.data, "refresh", 7) == 0){
 			flushcache();
 			respond(r, nil);
@@ -356,7 +362,6 @@
 	"fpregs",	Xfpregs,	0666,
 	"kregs",	Xkregs,		0666,
 	"mem",		Xmem,		0666,
-	"note",		Xnote,		0222,
 	"proc",		Xproc,		0444,
 	"regs",		Xregs,		0666,
 	"text",		Xtext,		0444,
@@ -393,6 +398,9 @@
 	case 'p':
 		procname = EARGF(usage());
 		break;
+	case 's':
+		srvname = EARGF(usage());
+		break;
 	case 't':
 		textfile = EARGF(usage());
 		break;
@@ -423,7 +431,7 @@
 	for(i=0; i<nelem(tab); i++)
 		closefile(createfile(dir, tab[i].s, "rdbfs", tab[i].mode, (void*)tab[i].id));
 	closefile(dir);
-	threadpostmountsrv(&fs, nil, "/proc", MBEFORE);
+	threadpostmountsrv(&fs, srvname, "/proc", MBEFORE);
 	exits(0);
 }
 
--- /sys/man/4/rdbfs	Thu Jun 13 05:07:55 2013
+++ /sys/man/4/rdbfs	Thu Jun 13 05:07:55 2013
@@ -11,6 +11,10 @@
 .I pid
 ]
 [
+.B -s
+.I srvname
+]
+[
 .B -t
 .I text
 ]
@@ -28,6 +32,15 @@
 .I device
 (default 
 .BR /dev/eia0 ).
+If the
+.B -s
+option is given,
+.I rdbfs
+will post its channel in
+.BI /srv/ srvname
+(see
+.IR srv (3)),
+allowing the session to be shared or reattached later.
 .PP
 The 
 .B text