--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/process-unix.c	Mon Aug 13 11:28:15 2007 +0200
@@ -0,0 +1,1764 @@
+/* Asynchronous subprocess implementation for UNIX
+   Copyright (C) 1985, 1986, 1987, 1988, 1992, 1993, 1994, 1995
+   Free Software Foundation, Inc.
+   Copyright (C) 1995 Sun Microsystems, Inc.
+   Copyright (C) 1995, 1996 Ben Wing.
+
+This file is part of XEmacs.
+
+XEmacs is free software; you can redistribute it and/or modify it
+under the terms of the GNU General Public License as published by the
+Free Software Foundation; either version 2, or (at your option) any
+later version.
+
+XEmacs is distributed in the hope that it will be useful, but WITHOUT
+ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with XEmacs; see the file COPYING.  If not, write to
+the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA.  */
+
+/* This file has been Mule-ized except for `start-process-internal',
+   `open-network-stream-internal' and `open-multicast-group-internal'. */
+
+/* This file has been split into process.c and process-unix.c by
+   Kirill M. Katsnelson <kkm@kis.ru>, so please bash him and not
+   the original author(s) */
+
+#include <config.h>
+
+#if !defined (NO_SUBPROCESSES)
+
+/* The entire file is within this conditional */
+
+#include "lisp.h"
+
+#include "buffer.h"
+#include "events.h"
+#include "frame.h"
+#include "hash.h"
+#include "lstream.h"
+#include "opaque.h"
+#include "process.h"
+#include "procimpl.h"
+#include "sysdep.h"
+#include "window.h"
+#ifdef FILE_CODING
+#include "file-coding.h"
+#endif
+
+#include <setjmp.h>
+#include "sysfile.h"
+#include "sysproc.h"
+#include "systime.h"
+#include "syssignal.h" /* Always include before systty.h */
+#include "systty.h"
+#include "syswait.h"
+
+
+/*
+ * Implementation-specific data. Pointed to by Lisp_Process->process_data
+ */
+
+struct unix_process_data
+{
+  /* Non-0 if this is really a ToolTalk channel. */
+  int connected_via_filedesc_p;
+  /* Descriptor by which we read from this process.  -1 for dead process */
+  int infd;
+  /* Descriptor for the tty which this process is using.
+     -1 if we didn't record it (on some systems, there's no need).  */
+  int subtty;
+  /* Name of subprocess terminal. */
+  Lisp_Object tty_name;
+  /* Non-false if communicating through a pty.  */
+  char pty_flag;
+};
+
+#define UNIX_DATA(p) ((struct unix_process_data*)((p)->process_data))
+
+#ifdef HAVE_PTYS
+/* The file name of the pty opened by allocate_pty.  */
+
+static char pty_name[24];
+#endif
+
+
+
+/**********************************************************************/
+/*                    Static helper routines                          */
+/**********************************************************************/
+
+static SIGTYPE
+close_safely_handler (int signo)
+{
+  EMACS_REESTABLISH_SIGNAL (signo, close_safely_handler);
+  SIGRETURN;
+}
+
+static void
+close_safely (int fd)
+{
+  stop_interrupts ();
+  signal (SIGALRM, close_safely_handler);
+  alarm (1);
+  close (fd);
+  alarm (0);
+  start_interrupts ();
+}
+
+static void
+close_descriptor_pair (int in, int out)
+{
+  if (in >= 0)
+    close (in);
+  if (out != in && out >= 0)
+    close (out);
+}
+
+/* Close all descriptors currently in use for communication
+   with subprocess.  This is used in a newly-forked subprocess
+   to get rid of irrelevant descriptors.  */
+
+static int
+close_process_descs_mapfun (CONST void* key, void* contents, void* arg)
+{
+  Lisp_Object proc;
+  CVOID_TO_LISP (proc, contents);
+  event_stream_delete_stream_pair (XPROCESS(proc)->pipe_instream,
+				   XPROCESS(proc)->pipe_outstream);
+  return 0;
+}
+
+/* #### This function is currently called from child_setup
+   in callproc.c. It should become static though - kkm */
+void
+close_process_descs (void)
+{
+  maphash (close_process_descs_mapfun, usid_to_process, 0);
+}
+
+/* connect to an existing file descriptor.  This is very similar to
+   open-network-stream except that it assumes that the connection has
+   already been initialized.  It is currently used for ToolTalk
+   communication. */
+
+/* This function used to be visible on the Lisp level, but there is no
+   real point in doing that.  Here is the doc string:
+
+  "Connect to an existing file descriptor.\n\
+Returns a subprocess-object to represent the connection.\n\
+Input and output work as for subprocesses; `delete-process' closes it.\n\
+Args are NAME BUFFER INFD OUTFD.\n\
+NAME is name for process.  It is modified if necessary to make it unique.\n\
+BUFFER is the buffer (or buffer-name) to associate with the process.\n\
+ Process output goes at end of that buffer, unless you specify\n\
+ an output stream or filter function to handle the output.\n\
+ BUFFER may be also nil, meaning that this process is not associated\n\
+ with any buffer\n\
+INFD and OUTFD specify the file descriptors to use for input and\n\
+ output, respectively."
+*/
+
+Lisp_Object
+connect_to_file_descriptor (Lisp_Object name, Lisp_Object buffer,
+			    Lisp_Object infd, Lisp_Object outfd)
+{
+  /* This function can GC */
+  Lisp_Object proc;
+  int inch;
+
+  CHECK_STRING (name);
+  CHECK_INT (infd);
+  CHECK_INT (outfd);
+
+  inch = XINT (infd);
+  if (get_process_from_usid (FD_TO_USID(inch)))
+    error ("There is already a process connected to fd %d", inch);
+  if (!NILP (buffer))
+    buffer = Fget_buffer_create (buffer);
+  proc = make_process_internal (name);
+
+  XPROCESS (proc)->pid = Fcons (infd, name);
+  XPROCESS (proc)->buffer = buffer;
+  init_process_io_handles (XPROCESS (proc), (void*)inch, (void*)XINT (outfd), 0);
+  UNIX_DATA (XPROCESS (proc))->connected_via_filedesc_p = 1;
+
+  event_stream_select_process (XPROCESS (proc));
+
+  return proc;
+}
+
+#ifdef HAVE_PTYS
+
+/* Open an available pty, returning a file descriptor.
+   Return -1 on failure.
+   The file name of the terminal corresponding to the pty
+   is left in the variable pty_name.  */
+
+static int
+allocate_pty (void)
+{
+#ifndef PTY_OPEN
+  struct stat stb;
+
+  /* Some systems name their pseudoterminals so that there are gaps in
+     the usual sequence - for example, on HP9000/S700 systems, there
+     are no pseudoterminals with names ending in 'f'.  So we wait for
+     three failures in a row before deciding that we've reached the
+     end of the ptys.  */
+  int failed_count = 0;
+#endif
+  int fd;
+#ifndef HAVE_GETPT
+  int i;
+  int c;
+#endif
+
+#ifdef PTY_ITERATION
+  PTY_ITERATION
+#else
+  for (c = FIRST_PTY_LETTER; c <= 'z'; c++)
+    for (i = 0; i < 16; i++)
+#endif
+      {
+#ifdef PTY_NAME_SPRINTF
+	PTY_NAME_SPRINTF
+#else
+	sprintf (pty_name, "/dev/pty%c%x", c, i);
+#endif /* no PTY_NAME_SPRINTF */
+
+#ifdef PTY_OPEN
+	PTY_OPEN;
+#else /* no PTY_OPEN */
+#ifdef IRIS
+	/* Unusual IRIS code */
+ 	*ptyv = open ("/dev/ptc", O_RDWR | O_NONBLOCK | OPEN_BINARY, 0);
+ 	if (fd < 0)
+ 	  return -1;
+	if (fstat (fd, &stb) < 0)
+	  return -1;
+#else /* not IRIS */
+	if (stat (pty_name, &stb) < 0)
+	  {
+	    failed_count++;
+	    if (failed_count >= 3)
+	      return -1;
+	  }
+	else
+	  failed_count = 0;
+	fd = open (pty_name, O_RDWR | O_NONBLOCK | OPEN_BINARY, 0);
+#endif /* not IRIS */
+#endif /* no PTY_OPEN */
+
+	if (fd >= 0)
+	  {
+	    /* check to make certain that both sides are available
+	       this avoids a nasty yet stupid bug in rlogins */
+#ifdef PTY_TTY_NAME_SPRINTF
+	    PTY_TTY_NAME_SPRINTF
+#else
+            sprintf (pty_name, "/dev/tty%c%x", c, i);
+#endif /* no PTY_TTY_NAME_SPRINTF */
+#if !defined(UNIPLUS) && !defined(HAVE_GETPT)
+	    if (access (pty_name, 6) != 0)
+	      {
+		close (fd);
+#if !defined(IRIS) && !defined(__sgi)
+		continue;
+#else
+		return -1;
+#endif /* IRIS */
+	      }
+#endif /* not UNIPLUS */
+	    setup_pty (fd);
+	    return fd;
+	  }
+      }
+  return -1;
+}
+#endif /* HAVE_PTYS */
+
+static int
+create_bidirectional_pipe (int *inchannel, int *outchannel,
+			   volatile int *forkin, volatile int *forkout)
+{
+  int sv[2];
+
+#ifdef SKTPAIR
+  if (socketpair (AF_UNIX, SOCK_STREAM, 0, sv) < 0)
+    return -1;
+  *outchannel = *inchannel = sv[0];
+  *forkout = *forkin = sv[1];
+#else /* not SKTPAIR */
+  int temp;
+  temp = pipe (sv);
+  if (temp < 0) return -1;
+  *inchannel = sv[0];
+  *forkout = sv[1];
+  temp = pipe (sv);
+  if (temp < 0) return -1;
+  *outchannel = sv[1];
+  *forkin = sv[0];
+#endif /* not SKTPAIR */
+  return 0;
+}
+
+
+#ifdef HAVE_SOCKETS
+
+static int
+get_internet_address (Lisp_Object host, struct sockaddr_in *address,
+		      Error_behavior errb)
+{
+  struct hostent *host_info_ptr = NULL;
+#ifdef TRY_AGAIN
+  int count = 0;
+#endif
+
+  xzero (*address);
+
+  while (1)
+    {
+#ifdef TRY_AGAIN
+      if (count++ > 10) break;
+#ifndef BROKEN_CYGWIN
+      h_errno = 0;
+#endif
+#endif
+      /* Some systems can't handle SIGIO/SIGALARM in gethostbyname. */
+      slow_down_interrupts ();
+      host_info_ptr = gethostbyname ((char *) XSTRING_DATA (host));
+      speed_up_interrupts ();
+#ifdef TRY_AGAIN
+      if (! (host_info_ptr == 0 && h_errno == TRY_AGAIN))
+#endif
+	break;
+      Fsleep_for (make_int (1));
+    }
+  if (host_info_ptr)
+    {
+      address->sin_family = host_info_ptr->h_addrtype;
+      memcpy (&address->sin_addr, host_info_ptr->h_addr, host_info_ptr->h_length);
+    }
+  else
+    {
+      IN_ADDR numeric_addr;
+      /* Attempt to interpret host as numeric inet address */
+      numeric_addr = inet_addr ((char *) XSTRING_DATA (host));
+      if (NUMERIC_ADDR_ERROR)
+	{
+	  maybe_error (Qprocess, errb,
+		       "Unknown host \"%s\"", XSTRING_DATA (host));
+	  return 0;
+	}
+
+      /* There was some broken code here that called strlen() here
+	 on (char *) &numeric_addr and even sometimes accessed
+	 uninitialized data. */
+      address->sin_family = AF_INET;
+      * (IN_ADDR *) &address->sin_addr = numeric_addr;
+    }
+
+  return 1;
+}
+
+static void
+set_socket_nonblocking_maybe (int fd, int port, CONST char* proto)
+{
+#ifdef PROCESS_IO_BLOCKING
+  Lisp_Object tail;
+
+  for (tail = network_stream_blocking_port_list; CONSP (tail); tail = XCDR (tail))
+    {
+      Lisp_Object tail_port = XCAR (tail);
+
+      if (STRINGP (tail_port))
+	{
+	  struct servent *svc_info;
+	  CHECK_STRING (tail_port);
+	  svc_info = getservbyname ((char *) XSTRING_DATA (tail_port), proto);
+	  if ((svc_info != 0) && (svc_info->s_port == port))
+	    break;
+	  else
+	    continue;
+	}
+      else if (INTP (tail_port) && (htons ((unsigned short) XINT (tail_port)) == port))
+	break;
+    }
+
+  if (!CONSP (tail))
+    {
+      set_descriptor_non_blocking (fd);
+    }
+#else
+  set_descriptor_non_blocking (fd);
+#endif	/* PROCESS_IO_BLOCKING */
+}
+
+#endif /* HAVE_SOCKETS */
+
+/* Compute the Lisp form of the process status from
+   the numeric status that was returned by `wait'.  */
+
+static void
+update_status_from_wait_code (struct Lisp_Process *p, int *w_fmh)
+{
+  /* C compiler lossage when attempting to pass w directly */
+  int w = *w_fmh;
+
+  if (WIFSTOPPED (w))
+    {
+      p->status_symbol = Qstop;
+      p->exit_code = WSTOPSIG (w);
+      p->core_dumped = 0;
+    }
+  else if (WIFEXITED (w))
+    {
+      p->status_symbol = Qexit;
+      p->exit_code = WEXITSTATUS (w);
+      p->core_dumped = 0;
+    }
+  else if (WIFSIGNALED (w))
+    {
+      p->status_symbol = Qsignal;
+      p->exit_code = WTERMSIG (w);
+      p->core_dumped = WCOREDUMP (w);
+    }
+  else
+    {
+      p->status_symbol = Qrun;
+      p->exit_code = 0;
+    }
+}
+
+#ifdef SIGCHLD
+
+#define MAX_EXITED_PROCESSES 1000
+static volatile pid_t exited_processes[MAX_EXITED_PROCESSES];
+static volatile int exited_processes_status[MAX_EXITED_PROCESSES];
+static volatile int exited_processes_index;
+
+static volatile int sigchld_happened;
+
+/* On receipt of a signal that a child status has changed,
+ loop asking about children with changed statuses until
+ the system says there are no more.  All we do is record
+ the processes and wait status.
+
+ This function could be called from within the SIGCHLD
+ handler, so it must be completely reentrant.  When
+ not called from a SIGCHLD handler, BLOCK_SIGCHLD should
+ be non-zero so that SIGCHLD is blocked while this
+ function is running. (This is necessary so avoid
+ race conditions with the SIGCHLD_HAPPENED flag). */
+
+static void
+record_exited_processes (int block_sigchld)
+{
+  if (!sigchld_happened)
+    {
+      return;
+    }
+
+#ifdef EMACS_BLOCK_SIGNAL
+  if (block_sigchld)
+    EMACS_BLOCK_SIGNAL (SIGCHLD);
+#endif
+
+  while (sigchld_happened)
+    {
+      int pid;
+      int w;
+
+      /* Keep trying to get a status until we get a definitive result.  */
+      do
+	{
+	  errno = 0;
+#ifdef WNOHANG
+#  ifndef WUNTRACED
+#    define WUNTRACED 0
+#  endif /* not WUNTRACED */
+#  ifdef HAVE_WAITPID
+	  pid = waitpid ((pid_t) -1, &w, WNOHANG | WUNTRACED);
+#  else
+	  pid = wait3 (&w, WNOHANG | WUNTRACED, 0);
+#  endif
+#else /* not WNOHANG */
+	  pid = wait (&w);
+#endif /* not WNOHANG */
+	}
+      while (pid <= 0 && errno == EINTR);
+
+      if (pid <= 0)
+	break;
+
+      if (exited_processes_index < MAX_EXITED_PROCESSES)
+	{
+	  exited_processes[exited_processes_index] = pid;
+	  exited_processes_status[exited_processes_index] = w;
+	  exited_processes_index++;
+	}
+
+      /* On systems with WNOHANG, we just ignore the number
+	 of times that SIGCHLD was signalled, and keep looping
+	 until there are no more processes to wait on.  If we
+	 don't have WNOHANG, we have to rely on the count in
+	 SIGCHLD_HAPPENED. */
+#ifndef WNOHANG
+      sigchld_happened--;
+#endif /* not WNOHANG */
+    }
+
+  sigchld_happened = 0;
+
+  if (block_sigchld)
+    EMACS_UNBLOCK_SIGNAL (SIGCHLD);
+}
+
+/* For any processes that have changed status and are recorded
+   and such, update the corresponding struct Lisp_Process.
+   We separate this from record_exited_processes() so that
+   we never have to call this function from within a signal
+   handler.  We block SIGCHLD in case record_exited_processes()
+   is called from a signal handler. */
+
+/** USG WARNING:  Although it is not obvious from the documentation
+ in signal(2), on a USG system the SIGCLD handler MUST NOT call
+ signal() before executing at least one wait(), otherwise the handler
+ will be called again, resulting in an infinite loop.  The relevant
+ portion of the documentation reads "SIGCLD signals will be queued
+ and the signal-catching function will be continually reentered until
+ the queue is empty".  Invoking signal() causes the kernel to reexamine
+ the SIGCLD queue.   Fred Fish, UniSoft Systems Inc.
+
+ (Note that now this only applies in SYS V Release 2 and before.
+ On SYS V Release 3, we use sigset() to set the signal handler for
+ the first time, and so we don't have to reestablish the signal handler
+ in the handler below.  On SYS V Release 4, we don't get this weirdo
+ behavior when we use sigaction(), which we do use.) */
+
+static SIGTYPE
+sigchld_handler (int signo)
+{
+#ifdef OBNOXIOUS_SYSV_SIGCLD_BEHAVIOR
+  int old_errno = errno;
+
+  sigchld_happened++;
+  record_exited_processes (0);
+  errno = old_errno;
+#else
+  sigchld_happened++;
+#endif
+#ifdef HAVE_UNIXOID_EVENT_LOOP
+  signal_fake_event ();
+#endif
+  /* WARNING - must come after wait3() for USG systems */
+  EMACS_REESTABLISH_SIGNAL (signo, sigchld_handler);
+  SIGRETURN;
+}
+
+#endif /* SIGCHLD */
+
+#ifdef SIGNALS_VIA_CHARACTERS
+/* Get signal character to send to process if SIGNALS_VIA_CHARACTERS */
+
+static int
+process_signal_char (int tty_fd, int signo)
+{
+  /* If it's not a tty, pray that these default values work */
+  if (!isatty(tty_fd)) {
+#define CNTL(ch) (037 & (ch))
+    switch (signo)
+      {
+      case SIGINT:  return CNTL('C');
+      case SIGQUIT: return CNTL('\\');
+#ifdef SIGTSTP
+      case SIGTSTP: return CNTL('Z');
+#endif
+      }
+  }
+
+#ifdef HAVE_TERMIOS
+  /* TERMIOS is the latest and bestest, and seems most likely to work.
+     If the system has it, use it. */
+  {
+    struct termios t;
+    tcgetattr (tty_fd, &t);
+    switch (signo)
+      {
+      case SIGINT:  return t.c_cc[VINTR];
+      case SIGQUIT: return t.c_cc[VQUIT];
+#if defined(SIGTSTP) && defined(VSUSP)
+      case SIGTSTP: return t.c_cc[VSUSP];
+#endif
+      }
+  }
+
+# elif defined (TIOCGLTC) && defined (TIOCGETC) /* not HAVE_TERMIOS */
+  {
+    /* On Berkeley descendants, the following IOCTL's retrieve the
+       current control characters.  */
+    struct tchars c;
+    struct ltchars lc;
+    switch (signo)
+      {
+      case SIGINT:  ioctl (tty_fd, TIOCGETC, &c);  return c.t_intrc;
+      case SIGQUIT: ioctl (tty_fd, TIOCGETC, &c);  return c.t_quitc;
+#  ifdef SIGTSTP
+      case SIGTSTP: ioctl (tty_fd, TIOCGLTC, &lc); return lc.t_suspc;
+#  endif /* SIGTSTP */
+      }
+  }
+
+# elif defined (TCGETA) /* ! defined (TIOCGLTC) && defined (TIOCGETC) */
+  {
+    /* On SYSV descendants, the TCGETA ioctl retrieves the current
+       control characters.  */
+    struct termio t;
+    ioctl (tty_fd, TCGETA, &t);
+    switch (signo) {
+    case SIGINT:  return t.c_cc[VINTR];
+    case SIGQUIT: return t.c_cc[VQUIT];
+#  ifdef SIGTSTP
+    case SIGTSTP: return t.c_cc[VSWTCH];
+#  endif /* SIGTSTP */
+    }
+  }
+# else /* ! defined (TCGETA) */
+#error ERROR! Using SIGNALS_VIA_CHARACTERS, but not HAVE_TERMIOS || (TIOCGLTC && TIOCGETC) || TCGETA
+  /* If your system configuration files define SIGNALS_VIA_CHARACTERS,
+     you'd better be using one of the alternatives above!  */
+# endif /* ! defined (TCGETA) */
+  return '\0';
+}
+#endif /* SIGNALS_VIA_CHARACTERS */
+
+
+
+
+/**********************************************************************/
+/*              Process implementation methods                        */
+/**********************************************************************/
+
+/*
+ * Allocate and initialize Lisp_Process->process_data
+ */
+
+static void
+unix_alloc_process_data (struct Lisp_Process *p)
+{
+  p->process_data = xnew (struct unix_process_data);
+
+  UNIX_DATA(p)->connected_via_filedesc_p = 0;
+  UNIX_DATA(p)->infd   = -1;
+  UNIX_DATA(p)->subtty = -1;
+  UNIX_DATA(p)->tty_name = Qnil;
+  UNIX_DATA(p)->pty_flag = 0;
+}
+
+/*
+ * Mark any Lisp objects in Lisp_Process->process_data
+ */
+
+static void
+unix_mark_process_data (struct Lisp_Process *proc)
+{
+  mark_object (UNIX_DATA(proc)->tty_name);
+}
+
+/*
+ * Initialize XEmacs process implementation once
+ */
+
+#ifdef SIGCHLD
+static void
+unix_init_process (void)
+{
+#ifndef CANNOT_DUMP
+  if (! noninteractive || initialized)
+#endif
+    signal (SIGCHLD, sigchld_handler);
+}
+#endif /* SIGCHLD */
+
+/*
+ * Initialize any process local data. This is called when newly
+ * created process is connected to real OS file handles. The
+ * handles are generally represented by void* type, but are
+ * of type int (file descriptors) for UNIX
+ */
+
+static void
+unix_init_process_io_handles (struct Lisp_Process *p, void* in, void* out, int flags)
+{
+  UNIX_DATA(p)->infd = (int)in;
+}
+
+/*
+ * Fork off a subprocess. P is a pointer to a newly created subprocess
+ * object. If this function signals, the caller is responsible for
+ * deleting (and finalizing) the process object.
+ *
+ * The method must return PID of the new process, a (positive??? ####) number
+ * which fits into Lisp_Int. No return value indicates an error, the method
+ * must signal an error instead.
+ */
+
+static int
+unix_create_process (struct Lisp_Process *p,
+		     Lisp_Object *argv, int nargv,
+		     Lisp_Object program, Lisp_Object cur_dir)
+{
+  /* This function rewritten by ben@xemacs.org. */
+
+  int pid;
+  int inchannel  = -1;
+  int outchannel = -1;
+  /* Use volatile to protect variables from being clobbered by longjmp.  */
+  volatile int forkin   = -1;
+  volatile int forkout  = -1;
+  volatile int pty_flag = 0;
+
+#ifdef HAVE_PTYS
+  if (!NILP (Vprocess_connection_type))
+    {
+      /* find a new pty, open the master side, return the opened
+	 file handle, and store the name of the corresponding slave
+	 side in global variable pty_name. */
+      outchannel = inchannel = allocate_pty ();
+    }
+
+  if (inchannel >= 0)
+    {
+      /* You're "supposed" to now open the slave in the child.
+	 On some systems, we can open it here; this allows for
+	 better error checking. */
+#if !defined(USG)
+      /* On USG systems it does not work to open the pty's tty here
+	 and then close and reopen it in the child.  */
+#ifdef O_NOCTTY
+      /* Don't let this terminal become our controlling terminal
+	 (in case we don't have one).  */
+      forkout = forkin = open (pty_name, O_RDWR | O_NOCTTY | OPEN_BINARY, 0);
+#else
+      forkout = forkin = open (pty_name, O_RDWR | OPEN_BINARY, 0);
+#endif
+      if (forkin < 0)
+	goto io_failure;
+#endif /* not USG */
+      UNIX_DATA(p)->pty_flag = pty_flag = 1;
+    }
+  else
+#endif /* HAVE_PTYS */
+    if (create_bidirectional_pipe (&inchannel, &outchannel,
+				   &forkin, &forkout) < 0)
+      goto io_failure;
+
+#if 0
+  /* Replaced by close_process_descs */
+  set_exclusive_use (inchannel);
+  set_exclusive_use (outchannel);
+#endif
+
+  set_descriptor_non_blocking (inchannel);
+
+  /* Record this as an active process, with its channels.
+     As a result, child_setup will close Emacs's side of the pipes.  */
+  init_process_io_handles (p, (void*)inchannel, (void*)outchannel,
+			   pty_flag ? STREAM_PTY_FLUSHING : 0);
+  /* Record the tty descriptor used in the subprocess.  */
+  UNIX_DATA(p)->subtty = forkin;
+
+  {
+#if !defined(__CYGWIN32__)
+    /* child_setup must clobber environ on systems with true vfork.
+       Protect it from permanent change.  */
+    char **save_environ = environ;
+#endif
+
+    pid = fork ();
+    if (pid == 0)
+      {
+	/**** Now we're in the child process ****/
+	int xforkin = forkin;
+	int xforkout = forkout;
+
+	if (!pty_flag)
+	  EMACS_SEPARATE_PROCESS_GROUP ();
+#ifdef HAVE_PTYS
+	else
+	  {
+	    /* Disconnect the current controlling terminal, pursuant to
+	       making the pty be the controlling terminal of the process.
+	       Also put us in our own process group. */
+
+	    disconnect_controlling_terminal ();
+
+	    /* Open the pty connection and make the pty's terminal
+	       our controlling terminal.
+
+	       On systems with TIOCSCTTY, we just use it to set
+	       the controlling terminal.  On other systems, the
+	       first TTY we open becomes the controlling terminal.
+	       So, we end up with four possibilities:
+
+	       (1) on USG and TIOCSCTTY systems, we open the pty
+	           and use TIOCSCTTY.
+	       (2) on other USG systems, we just open the pty.
+	       (3) on non-USG systems with TIOCSCTTY, we
+	           just use TIOCSCTTY. (On non-USG systems, we
+		   already opened the pty in the parent process.)
+	       (4) on non-USG systems without TIOCSCTTY, we
+	           close the pty and reopen it.
+
+	       This would be cleaner if we didn't open the pty
+	       in the parent process, but doing it that way
+	       makes it possible to trap error conditions.
+	       It's harder to convey an error from the child
+	       process, and I don't feel like messing with
+	       this now. */
+
+	    /* There was some weirdo, probably wrong,
+	       conditionalization on RTU and UNIPLUS here.
+	       I deleted it.  So sue me. */
+
+	    /* SunOS has TIOCSCTTY but the close/open method
+	       also works. */
+
+#  if defined (USG) || !defined (TIOCSCTTY)
+	    /* Now close the pty (if we had it open) and reopen it.
+	       This makes the pty the controlling terminal of the
+	       subprocess.  */
+	    /* I wonder if close (open (pty_name, ...)) would work?  */
+	    if (xforkin >= 0)
+	      close (xforkin);
+	    xforkout = xforkin = open (pty_name, O_RDWR | OPEN_BINARY, 0);
+	    if (xforkin < 0)
+	      {
+		write (1, "Couldn't open the pty terminal ", 31);
+		write (1, pty_name, strlen (pty_name));
+		write (1, "\n", 1);
+		_exit (1);
+	      }
+#  endif /* USG or not TIOCSCTTY */
+
+	    /* Miscellaneous setup required for some systems.
+               Must be done before using tc* functions on xforkin.
+               This guarantees that isatty(xforkin) is true. */
+
+# ifdef SETUP_SLAVE_PTY
+	    SETUP_SLAVE_PTY;
+# endif /* SETUP_SLAVE_PTY */
+
+#  ifdef TIOCSCTTY
+	    /* We ignore the return value
+	       because faith@cs.unc.edu says that is necessary on Linux.  */
+            assert (isatty (xforkin));
+	    ioctl (xforkin, TIOCSCTTY, 0);
+#  endif /* TIOCSCTTY */
+
+	    /* Change the line discipline. */
+
+# if defined (HAVE_TERMIOS) && defined (LDISC1)
+	    {
+	      struct termios t;
+              assert (isatty (xforkin));
+	      tcgetattr (xforkin, &t);
+	      t.c_lflag = LDISC1;
+	      if (tcsetattr (xforkin, TCSANOW, &t) < 0)
+		perror ("create_process/tcsetattr LDISC1 failed\n");
+	    }
+# elif defined (NTTYDISC) && defined (TIOCSETD)
+	    {
+	      /* Use new line discipline.  TIOCSETD is accepted and
+                 ignored on Sys5.4 systems with ttcompat. */
+	      int ldisc = NTTYDISC;
+              assert (isatty (xforkin));
+	      ioctl (xforkin, TIOCSETD, &ldisc);
+	    }
+# endif /* TIOCSETD & NTTYDISC */
+
+	    /* Make our process group be the foreground group
+	       of our new controlling terminal. */
+
+	    {
+	      int piddly = EMACS_GET_PROCESS_GROUP ();
+	      EMACS_SET_TTY_PROCESS_GROUP (xforkin, &piddly);
+	    }
+
+	    /* On AIX, we've disabled SIGHUP above once we start a
+	       child on a pty.  Now reenable it in the child, so it
+	       will die when we want it to.
+	       JV: This needs to be done ALWAYS as we might have inherited
+	       a SIG_IGN handling from our parent (nohup) and we are in new
+	       process group.
+	    */
+	    signal (SIGHUP, SIG_DFL);
+	  }
+
+	if (pty_flag)
+	  /* Set up the terminal characteristics of the pty. */
+	  child_setup_tty (xforkout);
+
+#endif /* HAVE_PTYS */
+
+	signal (SIGINT,  SIG_DFL);
+	signal (SIGQUIT, SIG_DFL);
+
+	{
+	  char *current_dir;
+	  char **new_argv = alloca_array (char *, nargv + 2);
+	  int i;
+
+	  /* Nothing below here GCs so our string pointers shouldn't move. */
+	  new_argv[0] = (char *) XSTRING_DATA (program);
+	  for (i = 0; i < nargv; i++)
+	    {
+	      CHECK_STRING (argv[i]);
+	      new_argv[i + 1] = (char *) XSTRING_DATA (argv[i]);
+	    }
+	  new_argv[i + 1] = 0;
+
+	  GET_C_STRING_FILENAME_DATA_ALLOCA (cur_dir, current_dir);
+
+	  child_setup (xforkin, xforkout, xforkout, new_argv, current_dir);
+	}
+
+      } /**** End of child code ****/
+
+    /**** Back in parent process ****/
+#if !defined(__CYGWIN32__)
+    environ = save_environ;
+#endif
+  }
+
+  if (pid < 0)
+    {
+      close_descriptor_pair (forkin, forkout);
+      report_file_error ("Doing fork", Qnil);
+    }
+
+  /* #### dmoore - why is this commented out, otherwise we leave
+     subtty = forkin, but then we close forkin just below. */
+  /* UNIX_DATA(p)->subtty = -1; */
+
+  /* If the subfork execv fails, and it exits,
+     this close hangs.  I don't know why.
+     So have an interrupt jar it loose.  */
+  if (forkin >= 0)
+    close_safely (forkin);
+  if (forkin != forkout && forkout >= 0)
+    close (forkout);
+
+#ifdef HAVE_PTYS
+  if (pty_flag)
+    UNIX_DATA (p)->tty_name = build_string (pty_name);
+  else
+#endif
+    UNIX_DATA (p)->tty_name = Qnil;
+
+  /* Notice that SIGCHLD was not blocked. (This is not possible on
+     some systems.) No biggie if SIGCHLD occurs right around the
+     time that this call happens, because SIGCHLD() does not actually
+     deselect the process (that doesn't occur until the next time
+     we're waiting for an event, when status_notify() is called). */
+  return pid;
+
+io_failure:
+  {
+    int save_errno = errno;
+    close_descriptor_pair (forkin, forkout);
+    close_descriptor_pair (inchannel, outchannel);
+    errno = save_errno;
+    report_file_error ("Opening pty or pipe", Qnil);
+    return 0; /* not reached */
+  }
+}
+
+/* Return nonzero if this process is a ToolTalk connection. */
+
+static int
+unix_tooltalk_connection_p (struct Lisp_Process *p)
+{
+  return UNIX_DATA(p)->connected_via_filedesc_p;
+}
+
+/* This is called to set process' virtual terminal size */
+
+static int
+unix_set_window_size (struct Lisp_Process* p, int cols, int rows)
+{
+  return set_window_size (UNIX_DATA(p)->infd, cols, rows);
+}
+
+/*
+ * This method is called to update status fields of the process
+ * structure. If the process has not existed, this method is
+ * expected to do nothing.
+ *
+ * The method is called only for real child processes.
+ */
+
+#ifdef HAVE_WAITPID
+static void
+unix_update_status_if_terminated (struct Lisp_Process* p)
+{
+  int w;
+#ifdef SIGCHLD
+  EMACS_BLOCK_SIGNAL (SIGCHLD);
+#endif
+  if (waitpid (XINT (p->pid), &w, WNOHANG) == XINT (p->pid))
+    {
+      p->tick++;
+      update_status_from_wait_code (p, &w);
+    }
+#ifdef SIGCHLD
+  EMACS_UNBLOCK_SIGNAL (SIGCHLD);
+#endif
+}
+#endif
+
+/*
+ * Update status of all exited processes. Called when SIGCLD has signaled.
+ */
+
+#ifdef SIGCHLD
+static void
+unix_reap_exited_processes (void)
+{
+  int i;
+  struct Lisp_Process *p;
+
+#ifndef OBNOXIOUS_SYSV_SIGCLD_BEHAVIOR
+  record_exited_processes (1);
+#endif
+
+  if (exited_processes_index <= 0)
+    {
+      return;
+    }
+
+#ifdef  EMACS_BLOCK_SIGNAL
+  EMACS_BLOCK_SIGNAL (SIGCHLD);
+#endif
+  for (i = 0; i < exited_processes_index; i++)
+    {
+      int pid = exited_processes[i];
+      int w = exited_processes_status[i];
+
+      /* Find the process that signaled us, and record its status.  */
+
+      p = 0;
+      {
+        Lisp_Object tail;
+	LIST_LOOP (tail, Vprocess_list)
+	  {
+	    Lisp_Object proc = XCAR (tail);
+	    p = XPROCESS (proc);
+	    if (INTP (p->pid) && XINT (p->pid) == pid)
+	      break;
+	    p = 0;
+	  }
+      }
+
+      if (p)
+	{
+	  /* Change the status of the process that was found.  */
+	  p->tick++;
+	  process_tick++;
+	  update_status_from_wait_code (p, &w);
+
+          /* If process has terminated, stop waiting for its output.  */
+	  if (WIFSIGNALED (w) || WIFEXITED (w))
+	    {
+	      if (!NILP(p->pipe_instream))
+		{
+		  /* We can't just call event_stream->unselect_process_cb (p)
+		     here, because that calls XtRemoveInput, which is not
+		     necessarily reentrant, so we can't call this at interrupt
+		     level.
+		   */
+		}
+	    }
+	}
+      else
+	{
+          /* There was no asynchronous process found for that id.  Check
+	     if we have a synchronous process. Only set sync process status
+	     if there is one, so we work OK with the waitpid() call in
+	     wait_for_termination(). */
+	  if (synch_process_alive != 0)
+	    { /* Set the global sync process status variables. */
+	      synch_process_alive = 0;
+
+	      /* Report the status of the synchronous process.  */
+	      if (WIFEXITED (w))
+		synch_process_retcode = WEXITSTATUS (w);
+	      else if (WIFSIGNALED (w))
+		synch_process_death = signal_name (WTERMSIG (w));
+	    }
+        }
+    }
+
+  exited_processes_index = 0;
+
+  EMACS_UNBLOCK_SIGNAL (SIGCHLD);
+}
+#endif /* SIGCHLD */
+
+/*
+ * Stuff the entire contents of LSTREAM to the process output pipe
+ */
+
+static JMP_BUF send_process_frame;
+
+static SIGTYPE
+send_process_trap (int signum)
+{
+  EMACS_REESTABLISH_SIGNAL (signum, send_process_trap);
+  EMACS_UNBLOCK_SIGNAL (signum);
+  LONGJMP (send_process_frame, 1);
+}
+
+static void
+unix_send_process (Lisp_Object proc, struct lstream* lstream)
+{
+  /* Use volatile to protect variables from being clobbered by longjmp.  */
+  SIGTYPE (*volatile old_sigpipe) (int) = 0;
+  volatile Lisp_Object vol_proc = proc;
+  struct Lisp_Process *volatile p = XPROCESS (proc);
+
+  if (!SETJMP (send_process_frame))
+    {
+      /* use a reasonable-sized buffer (somewhere around the size of the
+	 stream buffer) so as to avoid inundating the stream with blocked
+	 data. */
+      Bufbyte chunkbuf[512];
+      Bytecount chunklen;
+
+      while (1)
+	{
+	  ssize_t writeret;
+
+	  chunklen = Lstream_read (lstream, chunkbuf, 512);
+	  if (chunklen <= 0)
+	    break; /* perhaps should abort() if < 0?
+		      This should never happen. */
+	  old_sigpipe =
+	    (SIGTYPE (*) (int)) signal (SIGPIPE, send_process_trap);
+	  /* Lstream_write() will never successfully write less than
+	     the amount sent in.  In the worst case, it just buffers
+	     the unwritten data. */
+	  writeret = Lstream_write (XLSTREAM (DATA_OUTSTREAM(p)), chunkbuf,
+				    chunklen);
+	  signal (SIGPIPE, old_sigpipe);
+	  if (writeret < 0)
+	    /* This is a real error.  Blocking errors are handled
+	       specially inside of the filedesc stream. */
+	    report_file_error ("writing to process", list1 (proc));
+	  while (Lstream_was_blocked_p (XLSTREAM (p->pipe_outstream)))
+	    {
+	      /* Buffer is full.  Wait, accepting input;
+		 that may allow the program
+		 to finish doing output and read more.  */
+	      Faccept_process_output (Qnil, make_int (1), Qnil);
+	      old_sigpipe =
+		(SIGTYPE (*) (int)) signal (SIGPIPE, send_process_trap);
+	      Lstream_flush (XLSTREAM (p->pipe_outstream));
+	      signal (SIGPIPE, old_sigpipe);
+	    }
+	}
+    }
+  else
+    { /* We got here from a longjmp() from the SIGPIPE handler */
+      signal (SIGPIPE, old_sigpipe);
+      /* Close the file lstream so we don't attempt to write to it further */
+      /* #### There is controversy over whether this might cause fd leakage */
+      /*      my tests say no. -slb */
+      XLSTREAM (p->pipe_outstream)->flags &= ~LSTREAM_FL_IS_OPEN;
+      p->status_symbol = Qexit;
+      p->exit_code = 256; /* #### SIGPIPE ??? */
+      p->core_dumped = 0;
+      p->tick++;
+      process_tick++;
+      deactivate_process (*((Lisp_Object *) (&vol_proc)));
+      error ("SIGPIPE raised on process %s; closed it",
+	     XSTRING_DATA (p->name));
+    }
+
+  old_sigpipe = (SIGTYPE (*) (int)) signal (SIGPIPE, send_process_trap);
+  Lstream_flush (XLSTREAM (DATA_OUTSTREAM(p)));
+  signal (SIGPIPE, old_sigpipe);
+}
+
+/*
+ * Send EOF to the process. The default implementation simply
+ * closes the output stream. The method must return 0 to call
+ * the default implementation, or 1 if it has taken all care about
+ * sending EOF to the process.
+ */
+
+static int
+unix_process_send_eof (Lisp_Object proc)
+{
+  if (!UNIX_DATA (XPROCESS (proc))->pty_flag)
+    return 0;
+
+  /* #### get_eof_char simply doesn't return the correct character
+     here.  Maybe it is needed to determine the right eof
+     character in init_process_io_handles but here it simply screws
+     things up. */
+#if 0
+  Bufbyte eof_char = get_eof_char (XPROCESS (proc));
+  send_process (proc, Qnil, &eof_char, 0, 1);
+#else
+  send_process (proc, Qnil, (CONST Bufbyte *) "\004", 0, 1);
+#endif
+  return 1;
+}
+
+/*
+ * Called before the process is deactivated. The process object
+ * is not immediately finalized, just undergoes a transition to
+ * inactive state.
+ *
+ * The return value is a unique stream ID, as returned by
+ * event_stream_delete_stream_pair
+ *
+ * In the lack of this method, only event_stream_delete_stream_pair
+ * is called on both I/O streams of the process.
+ *
+ * The UNIX version guards this by ignoring possible SIGPIPE.
+ */
+
+static USID
+unix_deactivate_process (struct Lisp_Process *p)
+{
+  SIGTYPE (*old_sigpipe) (int) = 0;
+  USID usid;
+
+  if (UNIX_DATA(p)->infd >= 0)
+    flush_pending_output (UNIX_DATA(p)->infd);
+
+  /* closing the outstream could result in SIGPIPE, so ignore it. */
+  old_sigpipe = (SIGTYPE (*) (int)) signal (SIGPIPE, SIG_IGN);
+  usid = event_stream_delete_stream_pair (p->pipe_instream, p->pipe_outstream);
+  signal (SIGPIPE, old_sigpipe);
+
+  UNIX_DATA(p)->infd  = -1;
+
+  return usid;
+}
+
+/* send a signal number SIGNO to PROCESS.
+   CURRENT_GROUP means send to the process group that currently owns
+   the terminal being used to communicate with PROCESS.
+   This is used for various commands in shell mode.
+   If NOMSG is zero, insert signal-announcements into process's buffers
+   right away.
+
+   If we can, we try to signal PROCESS by sending control characters
+   down the pty.  This allows us to signal inferiors who have changed
+   their uid, for which killpg would return an EPERM error.
+
+   The method signals an error if the given SIGNO is not valid
+*/
+
+static void
+unix_kill_child_process (Lisp_Object proc, int signo,
+			 int current_group, int nomsg)
+{
+  int gid;
+  int no_pgrp = 0;
+  int kill_retval;
+  struct Lisp_Process *p = XPROCESS (proc);
+
+  if (!UNIX_DATA(p)->pty_flag)
+    current_group = 0;
+
+  /* If we are using pgrps, get a pgrp number and make it negative.  */
+  if (current_group)
+    {
+#ifdef SIGNALS_VIA_CHARACTERS
+      /* If possible, send signals to the entire pgrp
+	 by sending an input character to it.  */
+      {
+        char sigchar = process_signal_char(UNIX_DATA(p)->subtty, signo);
+        if (sigchar) {
+          send_process (proc, Qnil, (Bufbyte *) &sigchar, 0, 1);
+          return;
+        }
+      }
+#endif /* ! defined (SIGNALS_VIA_CHARACTERS) */
+
+#ifdef TIOCGPGRP
+      /* Get the pgrp using the tty itself, if we have that.
+	 Otherwise, use the pty to get the pgrp.
+	 On pfa systems, saka@pfu.fujitsu.co.JP writes:
+	 "TIOCGPGRP symbol defined in sys/ioctl.h at E50.
+	 But, TIOCGPGRP does not work on E50 ;-P works fine on E60"
+	 His patch indicates that if TIOCGPGRP returns an error, then
+	 we should just assume that p->pid is also the process group id.  */
+      {
+	int err;
+
+        err = ioctl ( (UNIX_DATA(p)->subtty != -1
+		       ? UNIX_DATA(p)->subtty
+		       : UNIX_DATA(p)->infd), TIOCGPGRP, &gid);
+
+#ifdef pfa
+	if (err == -1)
+	  gid = - XINT (p->pid);
+#endif /* ! defined (pfa) */
+      }
+      if (gid == -1)
+	no_pgrp = 1;
+      else
+	gid = - gid;
+#else /* ! defined (TIOCGPGRP ) */
+      /* Can't select pgrps on this system, so we know that
+	 the child itself heads the pgrp.  */
+      gid = - XINT (p->pid);
+#endif /* ! defined (TIOCGPGRP ) */
+    }
+  else
+    gid = - XINT (p->pid);
+
+  switch (signo)
+    {
+#ifdef SIGCONT
+    case SIGCONT:
+      p->status_symbol = Qrun;
+      p->exit_code = 0;
+      p->tick++;
+      process_tick++;
+      if (!nomsg)
+	status_notify ();
+      break;
+#endif /* ! defined (SIGCONT) */
+    case SIGINT:
+    case SIGQUIT:
+    case SIGKILL:
+      flush_pending_output (UNIX_DATA(p)->infd);
+      break;
+    }
+
+  /* If we don't have process groups, send the signal to the immediate
+     subprocess.  That isn't really right, but it's better than any
+     obvious alternative.  */
+  if (no_pgrp)
+    {
+      kill_retval = kill (XINT (p->pid), signo) ? errno : 0;
+    }
+  else
+    {
+      /* gid may be a pid, or minus a pgrp's number */
+#if defined (TIOCSIGNAL) || defined (TIOCSIGSEND)
+      if (current_group)
+	{
+#ifdef TIOCSIGNAL
+	  kill_retval = ioctl (UNIX_DATA(p)->infd, TIOCSIGNAL, signo);
+#else /* ! defined (TIOCSIGNAL) */
+	  kill_retval = ioctl (UNIX_DATA(p)->infd, TIOCSIGSEND, signo);
+#endif /* ! defined (TIOCSIGNAL) */
+	}
+      else
+	kill_retval = kill (- XINT (p->pid), signo) ? errno : 0;
+#else /* ! (defined (TIOCSIGNAL) || defined (TIOCSIGSEND)) */
+      kill_retval = EMACS_KILLPG (-gid, signo) ? errno : 0;
+#endif /* ! (defined (TIOCSIGNAL) || defined (TIOCSIGSEND)) */
+    }
+
+  if (kill_retval < 0 && errno == EINVAL)
+    error ("Signal number %d is invalid for this system", signo);
+}
+
+/*
+ * Kill any process in the system given its PID.
+ *
+ * Returns zero if a signal successfully sent, or
+ * negative number upon failure
+ */
+
+static int
+unix_kill_process_by_pid (int pid, int sigcode)
+{
+  return kill (pid, sigcode);
+}
+
+/*
+ * Return TTY name used to communicate with subprocess
+ */
+
+static Lisp_Object
+unix_get_tty_name (struct Lisp_Process *p)
+{
+  return UNIX_DATA (p)->tty_name;
+}
+
+/*
+ * Canonicalize host name HOST, and return its canonical form
+ *
+ * The default implementation just takes HOST for a canonical name.
+ */
+
+#ifdef HAVE_SOCKETS
+static Lisp_Object
+unix_canonicalize_host_name (Lisp_Object host)
+{
+  struct sockaddr_in address;
+
+  if (!get_internet_address (host, &address, ERROR_ME_NOT))
+    return host;
+
+  if (address.sin_family == AF_INET)
+    return build_string (inet_ntoa (address.sin_addr));
+  else
+    /* #### any clue what to do here? */
+    return host;
+}
+
+/* open a TCP network connection to a given HOST/SERVICE.  Treated
+   exactly like a normal process when reading and writing.  Only
+   differences are in status display and process deletion.  A network
+   connection has no PID; you cannot signal it.  All you can do is
+   deactivate and close it via delete-process */
+
+static void
+unix_open_network_stream (Lisp_Object name, Lisp_Object host, Lisp_Object service,
+			  Lisp_Object protocol, void** vinfd, void** voutfd)
+{
+  struct sockaddr_in address;
+  int inch;
+  int outch;
+  volatile int s;
+  volatile int port;
+  volatile int retry = 0;
+  int retval;
+
+  CHECK_STRING (host);
+
+  if (!EQ (protocol, Qtcp) && !EQ (protocol, Qudp))
+    error ("Unsupported protocol \"%s\"",
+	   string_data (symbol_name (XSYMBOL (protocol))));
+
+  if (INTP (service))
+    port = htons ((unsigned short) XINT (service));
+  else
+    {
+      struct servent *svc_info;
+      CHECK_STRING (service);
+
+      if (EQ (protocol, Qtcp))
+	  svc_info = getservbyname ((char *) XSTRING_DATA (service), "tcp");
+      else /* EQ (protocol, Qudp) */
+	  svc_info = getservbyname ((char *) XSTRING_DATA (service), "udp");
+
+      if (svc_info == 0)
+	error ("Unknown service \"%s\"", XSTRING_DATA (service));
+      port = svc_info->s_port;
+    }
+
+  get_internet_address (host, &address, ERROR_ME);
+  address.sin_port = port;
+
+  if (EQ (protocol, Qtcp))
+      s = socket (address.sin_family, SOCK_STREAM, 0);
+  else /* EQ (protocol, Qudp) */
+      s = socket (address.sin_family, SOCK_DGRAM, 0);
+
+  if (s < 0)
+    report_file_error ("error creating socket", list1 (name));
+
+  /* Turn off interrupts here -- see comments below.  There used to
+     be code which called bind_polling_period() to slow the polling
+     period down rather than turn it off, but that seems rather
+     bogus to me.  Best thing here is to use a non-blocking connect
+     or something, to check for QUIT. */
+
+  /* Comments that are not quite valid: */
+
+  /* Kernel bugs (on Ultrix at least) cause lossage (not just EINTR)
+     when connect is interrupted.  So let's not let it get interrupted.
+     Note we do not turn off polling, because polling is only used
+     when not interrupt_input, and thus not normally used on the systems
+     which have this bug.  On systems which use polling, there's no way
+     to quit if polling is turned off.  */
+
+  /* Slow down polling.  Some kernels have a bug which causes retrying
+     connect to fail after a connect.  */
+
+  slow_down_interrupts ();
+
+ loop:
+
+  /* A system call interrupted with a SIGALRM or SIGIO comes back
+     here, with can_break_system_calls reset to 0. */
+  SETJMP (break_system_call_jump);
+  if (QUITP)
+    {
+      speed_up_interrupts ();
+      REALLY_QUIT;
+      /* In case something really weird happens ... */
+      slow_down_interrupts ();
+    }
+
+  /* Break out of connect with a signal (it isn't otherwise possible).
+     Thus you don't get screwed with a hung network. */
+  can_break_system_calls = 1;
+  retval = connect (s, (struct sockaddr *) &address, sizeof (address));
+  can_break_system_calls = 0;
+  if (retval == -1 && errno != EISCONN)
+    {
+      int xerrno = errno;
+      if (errno == EINTR)
+	goto loop;
+      if (errno == EADDRINUSE && retry < 20)
+	{
+	  /* A delay here is needed on some FreeBSD systems,
+	     and it is harmless, since this retrying takes time anyway
+	     and should be infrequent.
+             `sleep-for' allowed for quitting this loop with interrupts
+             slowed down so it can't be used here.  Async timers should
+             already be disabled at this point so we can use `sleep'. */
+          sleep (1);
+	  retry++;
+	  goto loop;
+	}
+
+      close (s);
+
+      speed_up_interrupts ();
+
+      errno = xerrno;
+      report_file_error ("connection failed", list2 (host, name));
+    }
+
+  speed_up_interrupts ();
+
+  inch = s;
+  outch = dup (s);
+  if (outch < 0)
+    {
+      close (s); /* this used to be leaked; from Kyle Jones */
+      report_file_error ("error duplicating socket", list1 (name));
+    }
+
+  set_socket_nonblocking_maybe (inch, port, "tcp");
+
+  *vinfd = (void*)inch;
+  *voutfd = (void*)outch;
+}
+
+
+#ifdef HAVE_MULTICAST
+
+/* Didier Verna <verna@inf.enst.fr> Nov. 28 1997.
+
+   This function is similar to open-network-stream-internal, but provides a
+   mean to open an UDP multicast connection instead of a TCP one. Like in the
+   TCP case, the multicast connection will be seen as a sub-process,
+
+   Some notes:
+   - Normally, we should use sendto and recvfrom with non connected
+   sockets. The current code doesn't allow us to do this. In the future, it
+   would be a good idea to extend the process data structure in order to deal
+   properly with the different types network connections.
+   - For the same reason, when leaving a multicast group, it is better to make
+   a setsockopt - IP_DROP_MEMBERSHIP before closing the descriptors.
+   Unfortunately, this can't be done here because delete_process doesn't know
+   about the kind of connection we have. However, this is not such an
+   important issue.
+*/
+
+static void
+unix_open_multicast_group (Lisp_Object name, Lisp_Object dest, Lisp_Object port,
+			   Lisp_Object ttl, void** vinfd, void** voutfd)
+{
+  struct ip_mreq imr;
+  struct sockaddr_in sa;
+  struct protoent *udp;
+  int ws, rs;
+  int theport;
+  unsigned char thettl;
+  int one = 1; /* For REUSEADDR */
+  int ret;
+  volatile int retry = 0;
+
+  CHECK_STRING (dest);
+
+  CHECK_NATNUM (port);
+  theport = htons ((unsigned short) XINT (port));
+
+  CHECK_NATNUM (ttl);
+  thettl = (unsigned char) XINT (ttl);
+
+  if ((udp = getprotobyname ("udp")) == NULL)
+    error ("No info available for UDP protocol");
+
+  /* Init the sockets. Yes, I need 2 sockets. I couldn't duplicate one. */
+  if ((rs = socket (PF_INET, SOCK_DGRAM, udp->p_proto)) < 0)
+    report_file_error ("error creating socket", list1(name));
+  if ((ws = socket (PF_INET, SOCK_DGRAM, udp->p_proto)) < 0)
+    {
+      close (rs);
+      report_file_error ("error creating socket", list1(name));
+    }
+
+  /* This will be used for both sockets */
+  memset (&sa, 0, sizeof(sa));
+  sa.sin_family = AF_INET;
+  sa.sin_port = theport;
+  sa.sin_addr.s_addr = htonl (inet_addr ((char *) XSTRING_DATA (dest)));
+
+  /* Socket configuration for reading ------------------------ */
+
+  /* Multiple connections from the same machine. This must be done before
+     bind. If it fails, it shouldn't be fatal. The only consequence is that
+     people won't be able to connect twice from the same machine. */
+  if (setsockopt (rs, SOL_SOCKET, SO_REUSEADDR, (char *) &one, sizeof (one))
+      < 0)
+    warn_when_safe (Qmulticast, Qwarning, "Cannot reuse socket address");
+
+  /* bind socket name */
+  if (bind (rs, (struct sockaddr *)&sa, sizeof(sa)))
+    {
+      close (rs);
+      close (ws);
+      report_file_error ("error binding socket", list2(name, port));
+    }
+
+  /* join multicast group */
+  imr.imr_multiaddr.s_addr = htonl (inet_addr ((char *) XSTRING_DATA (dest)));
+  imr.imr_interface.s_addr = htonl (INADDR_ANY);
+  if (setsockopt (rs, IPPROTO_IP, IP_ADD_MEMBERSHIP,
+		 (char *) &imr, sizeof (struct ip_mreq)) < 0)
+    {
+      close (ws);
+      close (rs);
+      report_file_error ("error adding membership", list2(name, dest));
+    }
+
+  /* Socket configuration for writing ----------------------- */
+
+  /* Normally, there's no 'connect' in multicast, since we prefer to use
+     'sendto' and 'recvfrom'. However, in order to handle this connection in
+     the process-like way it is done for TCP, we must be able to use 'write'
+     instead of 'sendto'. Consequently, we 'connect' this socket. */
+
+  /* See open-network-stream-internal for comments on this part of the code */
+  slow_down_interrupts ();
+
+ loop:
+
+  /* A system call interrupted with a SIGALRM or SIGIO comes back
+     here, with can_break_system_calls reset to 0. */
+  SETJMP (break_system_call_jump);
+  if (QUITP)
+    {
+      speed_up_interrupts ();
+      REALLY_QUIT;
+      /* In case something really weird happens ... */
+      slow_down_interrupts ();
+    }
+
+  /* Break out of connect with a signal (it isn't otherwise possible).
+     Thus you don't get screwed with a hung network. */
+  can_break_system_calls = 1;
+  ret = connect (ws, (struct sockaddr *) &sa, sizeof (sa));
+  can_break_system_calls = 0;
+  if (ret == -1 && errno != EISCONN)
+    {
+      int xerrno = errno;
+
+      if (errno == EINTR)
+	goto loop;
+      if (errno == EADDRINUSE && retry < 20)
+	{
+	  /* A delay here is needed on some FreeBSD systems,
+	     and it is harmless, since this retrying takes time anyway
+	     and should be infrequent.
+	     `sleep-for' allowed for quitting this loop with interrupts
+	     slowed down so it can't be used here.  Async timers should
+	     already be disabled at this point so we can use `sleep'. */
+	  sleep (1);
+	  retry++;
+	  goto loop;
+	}
+
+      close (rs);
+      close (ws);
+      speed_up_interrupts ();
+
+      errno = xerrno;
+      report_file_error ("error connecting socket", list2(name, port));
+    }
+
+  speed_up_interrupts ();
+
+  /* scope */
+  if (setsockopt (ws, IPPROTO_IP, IP_MULTICAST_TTL,
+		  (char *) &thettl, sizeof (thettl)) < 0)
+    {
+      close (rs);
+      close (ws);
+      report_file_error ("error setting ttl", list2(name, ttl));
+    }
+
+  set_socket_nonblocking_maybe (rs, theport, "udp");
+
+  *vinfd = (void*)rs;
+  *voutfd = (void*)ws;
+}
+
+#endif /* HAVE_MULTICAST */
+
+#endif /* HAVE_SOCKETS */
+
+
+/**********************************************************************/
+/*                            Initialization                          */
+/**********************************************************************/
+
+void
+process_type_create_unix (void)
+{
+  PROCESS_HAS_METHOD (unix, alloc_process_data);
+  PROCESS_HAS_METHOD (unix, mark_process_data);
+#ifdef SIGCHLD
+  PROCESS_HAS_METHOD (unix, init_process);
+  PROCESS_HAS_METHOD (unix, reap_exited_processes);
+#endif
+  PROCESS_HAS_METHOD (unix, init_process_io_handles);
+  PROCESS_HAS_METHOD (unix, create_process);
+  PROCESS_HAS_METHOD (unix, tooltalk_connection_p);
+  PROCESS_HAS_METHOD (unix, set_window_size);
+#ifdef HAVE_WAITPID
+  PROCESS_HAS_METHOD (unix, update_status_if_terminated);
+#endif
+  PROCESS_HAS_METHOD (unix, send_process);
+  PROCESS_HAS_METHOD (unix, process_send_eof);
+  PROCESS_HAS_METHOD (unix, deactivate_process);
+  PROCESS_HAS_METHOD (unix, kill_child_process);
+  PROCESS_HAS_METHOD (unix, kill_process_by_pid);
+  PROCESS_HAS_METHOD (unix, get_tty_name);
+#ifdef HAVE_SOCKETS
+  PROCESS_HAS_METHOD (unix, canonicalize_host_name);
+  PROCESS_HAS_METHOD (unix, open_network_stream);
+#ifdef HAVE_MULTICAST
+  PROCESS_HAS_METHOD (unix, open_multicast_group);
+#endif
+#endif
+}
+
+void
+vars_of_process_unix (void)
+{
+  Fprovide (intern ("unix-processes"));
+}
+
+#endif /* !defined (NO_SUBPROCESSES) */