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/*
* pty_open_ctty: Open and establish controlling terminal.
* and utmp entries.
*
* Copyright 1990 by the Massachusetts Institute of Technology.
*
*
*Permission to use, copy, modify, and
* distribute this software and its documentation for any purpose and
* without fee is hereby granted, provided that the above copyright
* notice appear in all copies and that both that copyright notice and
* this permission notice appear in supporting documentation, and that
* the name of M.I.T. not be used in advertising or publicity pertaining
* to distribution of the software without specific, written prior
* permission. M.I.T. makes no representations about the suitability of
* this software for any purpose. It is provided "as is" without express
* or implied warranty.
*
*/
#include "mit-copyright.h"
#include <com_err.h>
#include "libpty.h"
#include "pty-int.h"
/*
* This routine will be called twice. It's not particularly important
* that the setsid() or TIOCSTTY ioctls succeed (they may not the
* second time), but rather that we have a controlling terminal at the
* end. It is assumed that vhangup doesn't exist and confuse the
* process's notion of controlling terminal on any system without
* TIOCNOTTY. That is, either vhangup() leaves the controlling
* terminal in tact, breaks the association completely, or the system
* provides TIOCNOTTY to get things back into a reasonable state. In
* practice, vhangup() either breaks the association completely or
* doesn't effect controlling terminals, so this condition is met.
*/
long
pty_open_ctty (slave, fd)
const char * slave;
int *fd;
{
int testfd, retval;
#ifdef HAVE_SETSID
(void) setsid();
#endif
#ifdef ultrix
/* The Ultrix (and other BSD tty drivers) require the process group
* to be zero, in order to acquire the new tty as a controlling tty. */
(void) setpgrp(0, 0);
#endif
/* First, dissociate from previous terminal */
if ( (retval = ptyint_void_association()) < 0 )
return retval;
*fd = open(slave, O_RDWR);
if (*fd < 0 )
return PTY_OPEN_SLAVE_OPENFAIL;
#ifdef ultrix
setpgrp(0, getpid());
#endif
#ifdef ultrix
setpgrp(0, getpid());
#endif
#ifdef TIOCSCTTY
ioctl(*fd, TIOCSTTY, 0); /* Don't check return.*/
#endif /* TIOCSTTY */
testfd = open("/dev/tty", O_RDWR|O_NDELAY);
if ( testfd < 0 )
{
close(*fd);
*fd = -1;
return PTY_OPEN_SLAVE_NOCTTY;
}
close(testfd);
return 0;
}
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