9pserve: add -c option

man/man4/9pserve.4

diff --git a/man/man4/9pserve.4 b/man/man4/9pserve.4
index 388f24b..cd34d93 100644
--- a/man/man4/9pserve.4
+++ b/man/man4/9pserve.4
@@ -12,6 +12,10 @@
 .I afid
 ]
 [
+.B -c
+.I addr
+]
+[
 .B -M
 .I msize
 ]
@@ -73,6 +77,11 @@
 .B -a
 option
 .TP
+.B -c
+multiplex clients onto a single connection to
+.IR addr ,
+instead of standard input and output
+.TP
 .B -M
 do not initialize the connection with a
 .B Tversion

src/cmd/9pserve.c

diff --git a/src/cmd/9pserve.c b/src/cmd/9pserve.c
index 88e0f6f..8e03843 100644
--- a/src/cmd/9pserve.c
+++ b/src/cmd/9pserve.c
@@ -136,7 +136,7 @@
 void
 usage(void)
 {
-	fprint(2, "usage: 9pserve [-lnv] [-A aname afid] [-M msize] address\n");
+	fprint(2, "usage: 9pserve [-lnv] [-A aname afid] [-c addr] [-M msize] address\n");
 	fprint(2, "\treads/writes 9P messages on stdin/stdout\n");
 	threadexitsall("usage");
 }
@@ -146,7 +146,7 @@
 void
 threadmain(int argc, char **argv)
 {
-	char *file, *x;
+	char *file, *x, *addr;
 	int fd;
 
 	x = getenv("verbose9pserve");
@@ -166,6 +166,15 @@
 		versioned = 1;
 		msize = atoi(EARGF(usage()));
 		break;
+	case 'c':
+		addr = netmkaddr(EARGF(usage()), "net", "9fs");
+		if((fd = dial(addr, nil, nil, nil)) < 0)
+			sysfatal("dial %s: %r", addr);
+		dup(fd, 0);
+		dup(fd, 1);
+		if(fd > 1)
+			close(fd);
+		break;
 	case 'n':
 		noauth = 1;
 		break;