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/*
* pty_open_ctty: Open and establish controlling terminal.
*
* Copyright 1995, 1996 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. Furthermore if you modify this software you must label
* your software as modified software and not distribute it in such a
* fashion that it might be confused with the original M.I.T. software.
* 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 <com_err.h>
#include "libpty.h"
#include "pty-int.h"
/*
* This function will be called twice. The first time it will acquire
* a controlling terminal from which to vhangup() or revoke() (see
* comments in open_slave.c); the second time, it will be to open the
* actual slave device for use by the application. We no longer call
* ptyint_void_association(), as that will be called in
* pty_open_slave() to avoid spurious calls to setsid(), etc.
*
* It is assumed that systems where vhangup() exists and does break
* the ctty association will allow the slave to be re-acquired as the
* ctty. Also, if revoke() or vhangup() doesn't break the ctty
* association, we assume that we can successfully reopen the slave.
*
* This function doesn't check whether we actually acquired the ctty;
* we assume that the caller will check that, or that it doesn't
* matter in the particular case.
*/
long
pty_open_ctty(const char *slave, int *fd)
{
#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. This may actually belong in
* ptyint_void_association().
*/
(void) setpgrp(0, 0);
#endif
*fd = open(slave, O_RDWR);
if (*fd < 0)
return PTY_OPEN_SLAVE_OPENFAIL;
#ifdef ultrix
setpgrp(0, getpid());
#endif
#ifdef TIOCSCTTY
ioctl(*fd, TIOCSCTTY, 0); /* Don't check return.*/
#endif /* TIOCSTTY */
return 0;
}
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