9042 multiples of tty streams modules cause weirdness
Reviewed by: Randy Fishel <randyf@sibernet.com>
Reviewed by: Carlos Neira <cneirabustos@gmail.com>
Approved by: Hans Rosenfeld <rosenfeld@grumpf.hope-2000.org>

@@ -24,10 +24,11 @@
 
 
 /*
  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
+ * Copyright 2018 OmniOS Community Edition (OmniOSce) Association.
  */
 
 /*
  * Description:
  *

@@ -60,11 +61,11 @@
 extern struct streamtab pteminfo;
 
 static struct fmodsw fsw = {
         "ptem",
         &pteminfo,
-        D_MTQPAIR | D_MP
+        D_MTQPAIR | D_MP | _D_SINGLE_INSTANCE
 };
 
 static struct modlstrmod modlstrmod = {
         &mod_strmodops, "pty hardware emulator", &fsw
 };