12306 XPG4v2 slave pty behaviour should generally be disabled
Reviewed by: Robert Mustacchi <rm@fingolfin.org>
Change-ID: I7ccd399c22866f34dd20c6bb9d28e77ba4e24c67

*** 22,33 ****
   * Copyright (c) 1988, 2010, Oracle and/or its affiliates. All rights reserved.
   */
  /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
  /*        All Rights Reserved   */
  
  
- 
  /*
   * Pseudo Terminal Master Driver.
   *
   * The pseudo-tty subsystem simulates a terminal connection, where the master
   * side represents the terminal and the slave represents the user process's
--- 22,35 ----
   * Copyright (c) 1988, 2010, Oracle and/or its affiliates. All rights reserved.
   */
  /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
  /*        All Rights Reserved   */
  
+ /*
+  * Copyright 2020 OmniOS Community Edition (OmniOSce) Association.
+  */
  
  /*
   * Pseudo Terminal Master Driver.
   *
   * The pseudo-tty subsystem simulates a terminal connection, where the master
   * side represents the terminal and the slave represents the user process's
*** 519,528 ****
--- 521,537 ----
                          /*FALLTHROUGH*/
                  case ISPTM:
                          DBG(("ack the UNLKPT/ISPTM\n"));
                          miocack(qp, mp, 0, 0);
                          break;
+                 case PTSSTTY:
+                         mutex_enter(&ptmp->pt_lock);
+                         ptmp->pt_state |= PTSTTY;
+                         mutex_exit(&ptmp->pt_lock);
+                         DBG(("ack PTSSTTY\n"));
+                         miocack(qp, mp, 0, 0);
+                         break;
                  case ZONEPT:
                  {
                          zoneid_t z;
                          int error;