Coverity CID 400833 UNINIT

[sxemacs] / src / sysdep.c

/* Interfaces to system-dependent kernel and library entries.
   Copyright (C) 1985-1988, 1992-1995 Free Software Foundation, Inc.
   Copyright (C) 1995 Tinker Systems.
   Copyright (C) 2007 Sebastian Freundt

This file is part of SXEmacs

SXEmacs 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 3 of the License, or
(at your option) any later version.

SXEmacs 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 this program.  If not, see <http://www.gnu.org/licenses/>. */


/* Synched up with: FSF 19.30 except for some Windows-NT crap. */

/* Substantially cleaned up by Ben Wing, Dec. 1994 / Jan. 1995. */

/* In this file, open, read and write refer to the system calls,
   not our sugared interfaces sys_open, sys_read and sys_write.
 */

#define DONT_ENCAPSULATE

#include <config.h>

#include "lisp.h"

/* ------------------------------- */
/*          basic includes         */
/* ------------------------------- */

#ifdef HAVE_TTY
#include "ui/TTY/console-tty.h" /* for stuff in stuff_char and
                                   others. Seriously in need of
                                   refactoring... */
#else
#include "syssignal.h"
#include "ui/systty.h"
#endif                          /* HAVE_TTY */

#include "ui/console-stream.h"

#include "buffer.h"
#include "events/events.h"
#include "ui/frame.h"
#include "ui/redisplay.h"
#include "process.h"
#include "sysdep.h"
#include "ui/window.h"

#include <setjmp.h>
#ifdef HAVE_LIBGEN_H            /* Must come before sysfile.h */
#include <libgen.h>
#endif
#include "sysfile.h"
#include "syswait.h"
#include "sysdir.h"
#include "systime.h"

#include "sysproc.h"

#include <sys/times.h>

/* ------------------------------- */
/*         TTY definitions         */
/* ------------------------------- */

#ifdef USG
#include <sys/utsname.h>
#if defined (TIOCGWINSZ) || defined (ISC4_0)
#ifdef NEED_SIOCTL
#include <sys/sioctl.h>
#endif
#ifdef NEED_PTEM_H
#include <sys/stream.h>
#include <sys/ptem.h>
#endif
#endif                          /* TIOCGWINSZ or ISC4_0 */
#endif                          /* USG */

/* LPASS8 is new in 4.3, and makes cbreak mode provide all 8 bits.  */
#ifndef LPASS8
#define LPASS8 0
#endif

#ifndef HAVE_H_ERRNO
int h_errno;
#endif

#ifdef HAVE_TTY

static int baud_convert[] =
#ifdef BAUD_CONVERT
    BAUD_CONVERT;
#else
{
        0, 50, 75, 110, 135, 150, 200, 300, 600, 1200,
        1800, 2400, 4800, 9600, 19200, 38400
};
#endif

#endif

#ifdef AIXHFT
static void hft_init(struct console *c);
static void hft_reset(struct console *c);
#include <sys/termio.h>
#endif
\f
/************************************************************************/
/*                         subprocess control                           */
/************************************************************************/

#ifdef HAVE_TTY

#ifdef SIGTSTP

/* Arrange for character C to be read as the next input from
   the terminal.  */
void stuff_char(struct console *con, int c)
{
        int input_fd;

        assert(CONSOLE_TTY_P(con));
        input_fd = CONSOLE_TTY_DATA(con)->infd;
/* Should perhaps error if in batch mode */
#ifdef TIOCSTI
        ioctl(input_fd, TIOCSTI, &c);
#else                           /* no TIOCSTI */
        error
            ("Cannot stuff terminal input characters in this version of Unix.");
#endif                          /* no TIOCSTI */
}

#endif                          /* SIGTSTP */

#endif                          /* HAVE_TTY */

void set_exclusive_use(int fd)
{
#ifdef FIOCLEX
        ioctl(fd, FIOCLEX, 0);
#endif
        /* Ok to do nothing if this feature does not exist */
}

void set_descriptor_non_blocking(int fd)
{
/* Stride people say it's a mystery why this is needed
   as well as the O_NDELAY, but that it fails without this.  */
        /* For AIX: Apparently need this for non-blocking reads on sockets.
           It seems that O_NONBLOCK applies only to FIFOs?  From
           lowry@watson.ibm.com (Andy Lowry). */
        /* #### Should this be conditionalized on FIONBIO? */
#if defined (STRIDE) || (defined (pfa) && defined (HAVE_PTYS)) || defined (AIX)
        {
                int one = 1;
                ioctl(fd, FIONBIO, &one);
        }
#endif

#ifdef F_SETFL
        fcntl(fd, F_SETFL, O_NONBLOCK);
#endif
}

#if defined (NO_SUBPROCESSES)

#ifdef BSD
void wait_without_blocking(void)
{
        wait3(0, WNOHANG | WUNTRACED, 0);
        synch_process_alive = 0;
}
#endif                          /* BSD */

#endif                          /* NO_SUBPROCESSES */

void wait_for_termination(int pid)
{
        /* #### With the new improved SIGCHLD handling stuff, there is much
           less danger of race conditions and some of the comments below
           don't apply.  This should be updated. */

#if defined (NO_SUBPROCESSES)
        while (1) {
                /* No need to be tricky like below; we can just call wait(). */
                /* #### should figure out how to write a wait_allowing_quit().
                   Since hardly any systems don't have subprocess support,
                   however, there doesn't seem to be much point. */
                if (wait(0) == pid)
                        return;
        }
#elif defined (HAVE_WAITPID)
        /* Note that, whenever any subprocess terminates (asynch. or synch.),
           the SIGCHLD handler will be called and it will call wait().  Thus
           we cannot just call wait() ourselves, and we can't block SIGCHLD
           and then call wait(), because then if an asynch.  process dies
           while we're waiting for our synch. process, Emacs will never
           notice that the asynch. process died.

           So, the general approach we take is to repeatedly block until a
           signal arrives, and then check if our process died using kill
           (pid, 0).  (We could also check the value of `synch_process_alive',
           since the SIGCHLD handler will reset that and we know that we're
           only being called on synchronous processes, but this approach is
           safer.  I don't trust the proper delivery of SIGCHLD.

           Note also that we cannot use any form of waitpid().  A loop with
           WNOHANG will chew up CPU time; better to use sleep().  A loop
           without WNOWAIT will screw up the SIGCHLD handler (actually this
           is not true, if you duplicate the exit-status-reaping code; see
           below).  A loop with WNOWAIT will result in a race condition if
           the process terminates between the process-status check and the
           call to waitpid(). */

        /* Formerly, immediate_quit was set around this function call, but
           that could lead to problems if the QUIT happened when SIGCHLD was
           blocked -- it would remain blocked.  Yet another reason why
           immediate_quit is a bad idea.  In any case, there is no reason to
           resort to this because either the SIGIO or the SIGALRM will stop
           the block in EMACS_WAIT_FOR_SIGNAL(). */

        /* Apparently there are bugs on some systems with the second method
           used below (the EMACS_BLOCK_SIGNAL method), whereby zombie
           processes get left around.  It appears in those cases that the
           SIGCHLD handler is never getting invoked.  It's not clear whether
           this is an Emacs bug or a kernel bug or both: on HPUX this
           problem is observed only with XEmacs, but under Solaris 2.4 all
           sorts of different programs have problems with zombies.  The
           method we use here does not require a working SIGCHLD (but will
           not break if it is working), and should be safe. */
        /*
           We use waitpid(), contrary to the remarks above.  There is no
           race condition, because the three situations when sigchld_handler
           is invoked should be handled OK:

           - handler invoked before waitpid(): In this case, subprocess
           status will be set by sigchld_handler.  waitpid() here will
           return -1 with errno set to ECHILD, which is a valid exit
           condition.

           - handler invoked during waitpid(): as above, except that errno
           here will be set to EINTR.  This will cause waitpid() to be
           called again, and this time it will exit with ECHILD.

           - handler invoked after waitpid(): The following code will reap
           the subprocess. In the handler, wait() will return -1 because
           there is no child to reap, and the handler will exit without
           modifying child subprocess status.  */
        int ret, status;

        /* Because the SIGCHLD handler can potentially reap the synchronous
           subprocess, we should take care of that.  */

        /* Will stay in the do loop as long as:
           1. Process is alive
           2. Ctrl-G is not pressed */
        do {
                QUIT;
                ret = waitpid(pid, &status, 0);
                /* waitpid returns 0 if the process is still alive. */
        }
        while (ret == 0 || (ret == -1 && errno == EINTR));

        if (ret == pid)
        {                       /* Success */
                /* Set synch process globals.  This is can also happen
                   in sigchld_handler, and that code is duplicated. */
                synch_process_alive = 0;
                if (WIFEXITED(status))
                        synch_process_retcode = WEXITSTATUS(status);
                else if (WIFSIGNALED(status))
                        synch_process_death = signal_name(WTERMSIG(status));
        }
        /* On exiting the loop, ret will be -1, with errno set to ECHILD if
           the child has already been reaped, e.g. in the signal handler.  */

        /* Otherwise, we've had some error condition here.
           Per POSIX, the only other possibilities are:
           - EFAULT (bus error accessing arg 2) or
           - EINVAL (incorrect arguments),
           which are both program bugs.

           Since implementations may add their own error indicators on top,
           we ignore it by default.  */
#elif defined (EMACS_BLOCK_SIGNAL) && !defined (BROKEN_WAIT_FOR_SIGNAL) && defined (SIGCHLD)
        while (1) {
                static int wait_debugging = 0;  /* Set nonzero to make following
                                                   function work under dbx (at least for bsd).  */
                QUIT;
                if (wait_debugging)
                        return;

                EMACS_BLOCK_SIGNAL(SIGCHLD);
                /* Block SIGCHLD from happening during this check,
                   to avoid race conditions. */
                if (kill(pid, 0) < 0) {
                        EMACS_UNBLOCK_SIGNAL(SIGCHLD);
                        return;
                } else
                        /* WARNING: Whatever this macro does *must* not allow SIGCHLD
                           to happen between the time that it's reenabled and when we
                           begin to block.  Otherwise we may end up blocking for a
                           signal that has already arrived and isn't coming again.
                           Can you say "race condition"?

                           I assume that the system calls sigpause() or sigsuspend()
                           to provide this atomicness.  If you're getting hangs in
                           sigpause()/sigsuspend(), then your OS doesn't implement
                           this properly (this applies under hpux9, for example).
                           Try defining BROKEN_WAIT_FOR_SIGNAL. */
                        EMACS_WAIT_FOR_SIGNAL(SIGCHLD);
        }
#else                           /* not HAVE_WAITPID and (not EMACS_BLOCK_SIGNAL or BROKEN_WAIT_FOR_SIGNAL) */
        /* This approach is kind of cheesy but is guaranteed(?!) to work
           for all systems. */
        while (1) {
                QUIT;
                if (kill(pid, 0) < 0)
                        return;
                emacs_sleep(1);
        }
#endif                          /* OS features */
}

#if !defined (NO_SUBPROCESSES)

/*
 *      flush any pending output
 *      (may flush input as well; it does not matter the way we use it)
 */

void flush_pending_output(int channel)
{
#ifdef HAVE_TERMIOS
        /* If we try this, we get hit with SIGTTIN, because
           the child's tty belongs to the child's pgrp. */
#elif defined (TCFLSH)
        ioctl(channel, TCFLSH, 1);
#elif defined (TIOCFLUSH)
        int zero = 0;
        /* 3rd arg should be ignored
           but some 4.2 kernels actually want the address of an int
           and nonzero means something different.  */
        ioctl(channel, TIOCFLUSH, &zero);
#endif
}

/*  Set up the terminal at the other end of a pseudo-terminal that
    we will be controlling an inferior through.
    It should not echo or do line-editing, since that is done
    in Emacs.  No padding needed for insertion into an Emacs buffer.  */

void child_setup_tty(int out)
{
        struct emacs_tty s;
        emacs_get_tty(out, &s);

#if defined (HAVE_TERMIO) || defined (HAVE_TERMIOS)
        assert(isatty(out));
        s.main.c_oflag |= OPOST;        /* Enable output postprocessing */
        s.main.c_oflag &= ~ONLCR;       /* Disable map of NL to CR-NL on output */
#ifdef NLDLY
        s.main.c_oflag &= ~(NLDLY | CRDLY | TABDLY | BSDLY | VTDLY | FFDLY);
        /* No output delays */
#endif
        s.main.c_lflag &= ~ECHO;        /* Disable echo */
        s.main.c_lflag |= ISIG; /* Enable signals */
#ifdef IUCLC
        s.main.c_iflag &= ~IUCLC;       /* Disable downcasing on input.  */
#endif
#ifdef OLCUC
        s.main.c_oflag &= ~OLCUC;       /* Disable upcasing on output.  */
#endif
        s.main.c_oflag &= ~TAB3;        /* Disable tab expansion */
#if defined (CSIZE) && defined (CS8)
        s.main.c_cflag = (s.main.c_cflag & ~CSIZE) | CS8;       /* Don't strip 8th bit */
#endif
#ifdef ISTRIP
        s.main.c_iflag &= ~ISTRIP;      /* Don't strip 8th bit on input */
#endif
#if 0
        /* Unnecessary as long as ICANON is set */
        s.main.c_cc[VMIN] = 1;  /* minimum number of characters to accept  */
        s.main.c_cc[VTIME] = 0; /* wait forever for at least 1 character  */
#endif                          /* 0 */

        s.main.c_lflag |= ICANON;       /* Enable erase/kill and eof processing */
        s.main.c_cc[VEOF] = 04; /* ensure that EOF is Control-D */
        s.main.c_cc[VERASE] = _POSIX_VDISABLE;  /* disable erase processing */
        s.main.c_cc[VKILL] = _POSIX_VDISABLE;   /* disable kill processing */

#ifdef HPUX
        s.main.c_cflag = (s.main.c_cflag & ~CBAUD) | B9600;     /* baud rate sanity */
#endif                          /* HPUX */

#ifdef AIX
#ifndef IBMR2AIX
        /* AIX enhanced edit loses NULs, so disable it. */
        s.main.c_line = 0;
        s.main.c_iflag &= ~ASCEDIT;
#endif                          /* IBMR2AIX */
        /* Also, PTY overloads NUL and BREAK.
           don't ignore break, but don't signal either, so it looks like NUL.
           This really serves a purpose only if running in an XTERM window
           or via TELNET or the like, but does no harm elsewhere.  */
        s.main.c_iflag &= ~IGNBRK;
        s.main.c_iflag &= ~BRKINT;
#endif                          /* AIX */
#ifdef SIGNALS_VIA_CHARACTERS
        /* TTY `special characters' are used in process_send_signal
           so set them here to something useful.  */
        s.main.c_cc[VQUIT] = '\\' & 037;        /* Control-\ */
        s.main.c_cc[VINTR] = 'C' & 037; /* Control-C */
        s.main.c_cc[VSUSP] = 'Z' & 037; /* Control-Z */
#else                           /* no TIOCGPGRP or no TIOCGLTC or no TIOCGETC */
        /* TTY `special characters' work better as signals, so disable
           character forms */
        s.main.c_cc[VQUIT] = _POSIX_VDISABLE;
        s.main.c_cc[VINTR] = _POSIX_VDISABLE;
        s.main.c_cc[VSUSP] = _POSIX_VDISABLE;
        s.main.c_lflag &= ~ISIG;
#endif                          /* no TIOCGPGRP or no TIOCGLTC or no TIOCGETC */
        s.main.c_cc[VEOL] = _POSIX_VDISABLE;
#if defined (CBAUD)
        /* <mdiers> #### This is not portable. ###
           POSIX does not specify CBAUD, and 4.4BSD does not have it.
           Instead, POSIX suggests to use cfset{i,o}speed().
           [cf. D. Lewine, POSIX Programmer's Guide, Chapter 8: Terminal
           I/O, O'Reilly 1991] */
        s.main.c_cflag = (s.main.c_cflag & ~CBAUD) | B9600;     /* baud rate sanity */
#else
        /* <mdiers> What to do upon failure? Just ignoring rc is probably
           not acceptable, is it? */
        if (cfsetispeed(&s.main, B9600) == -1)  /* ignore */
                ;
        if (cfsetospeed(&s.main, B9600) == -1)  /* ignore */
                ;
#endif                          /* defined (CBAUD) */

#else                           /* not HAVE_TERMIO */

        s.main.sg_flags &= ~(ECHO | CRMOD | ANYP | ALLDELAY | RAW | LCASE
                             | CBREAK | TANDEM);
        s.main.sg_flags |= LPASS8;
        s.main.sg_erase = 0377;
        s.main.sg_kill = 0377;
        s.lmode = LLITOUT | s.lmode;    /* Don't strip 8th bit */

#endif                          /* not HAVE_TERMIO */
        emacs_set_tty(out, &s, 0);

#ifdef RTU
        {
                int zero = 0;
                ioctl(out, FIOASYNC, &zero);
        }
#endif                          /* RTU */
}
#endif                          /* not NO_SUBPROCESSES */
\f
#if !defined (SIGTSTP) && !defined (USG_JOBCTRL)

#if defined(__STDC__) || defined(_MSC_VER)
#define SIG_PARAM_TYPE int
#else
#define SIG_PARAM_TYPE
#endif

/* Record a signal code and the handler for it.  */
struct save_signal {
        int code;
         SIGTYPE(*handler) (SIG_PARAM_TYPE);
};

static void save_signal_handlers(struct save_signal *saved_handlers)
{
        while (saved_handlers->code) {
                saved_handlers->handler
                    =
                    (SIGTYPE(*)(SIG_PARAM_TYPE)) signal(saved_handlers->code,
                                                        SIG_IGN);
                saved_handlers++;
        }
}

static void restore_signal_handlers(struct save_signal *saved_handlers)
{
        while (saved_handlers->code) {
                signal(saved_handlers->code, saved_handlers->handler);
                saved_handlers++;
        }
}

/* Fork a subshell.  */
static void sys_subshell(void)
{
        int pid;
        struct save_signal saved_handlers[5];
        Lisp_Object dir;
        unsigned char *str = 0;
        int len;
        struct gcpro gcpro1;

        saved_handlers[0].code = SIGINT;
        saved_handlers[1].code = SIGQUIT;
        saved_handlers[2].code = SIGTERM;
#ifdef SIGIO
        saved_handlers[3].code = SIGIO;
        saved_handlers[4].code = 0;
#else
        saved_handlers[3].code = 0;
#endif

        /* Mentioning current_buffer->buffer would mean including buffer.h,
           which somehow wedges the hp compiler.  So instead...  */

        if (NILP(Fboundp(Qdefault_directory)))
                goto xyzzy;
        dir = Fsymbol_value(Qdefault_directory);
        if (!STRINGP(dir))
                goto xyzzy;

        GCPRO1(dir);
        dir = Funhandled_file_name_directory(dir);
        dir = expand_and_dir_to_file(dir, Qnil);
        UNGCPRO;
        str = (unsigned char *)alloca(XSTRING_LENGTH(dir) + 2);
        len = XSTRING_LENGTH(dir);
        memcpy(str, XSTRING_DATA(dir), len);
        if (!IS_ANY_SEP(str[len - 1]))
                str[len++] = DIRECTORY_SEP;
        str[len] = 0;
      xyzzy:

        pid = fork();

        if (pid == -1)
                error("Can't spawn subshell");
        if (pid == 0)
        {
                char *sh = 0;

                if (sh == 0)
                        sh = (char *)egetenv("SHELL");
                if (sh == 0)
                        sh = "sh";

                /* Use our buffer's default directory for the subshell.  */
                if (str)
                        sys_chdir(str);

#if !defined (NO_SUBPROCESSES)
                close_process_descs();  /* Close Emacs's pipes/ptys */
#endif

#ifdef SET_EMACS_PRIORITY
                if (emacs_priority != 0)
                        nice(-emacs_priority);  /* Give the new shell the default priority */
#endif

                execlp(sh, sh, 0);
                write(1, "Can't execute subshell", 22);
                _exit(1);
        }

        save_signal_handlers(saved_handlers);
        synch_process_alive = 1;
        wait_for_termination(pid);
        restore_signal_handlers(saved_handlers);
}
#endif                          /* !defined (SIGTSTP) && !defined (USG_JOBCTRL) */
\f
/* Suspend the Emacs process; give terminal to its superior.  */
void sys_suspend(void)
{
#if defined (SIGTSTP)
        {
                int pgrp = EMACS_GET_PROCESS_GROUP();
                EMACS_KILLPG(pgrp, SIGTSTP);
        }

#elif defined (USG_JOBCTRL)
        /* If you don't know what this is don't mess with it */
        ptrace(0, 0, 0, 0);     /* set for ptrace - caught by csh */
        kill(getpid(), SIGQUIT);

#else                           /* No SIGTSTP or USG_JOBCTRL */

        /* On a system where suspending is not implemented,
           instead fork a subshell and let it talk directly to the terminal
           while we wait.  */
        sys_subshell();

#endif
}

/* Suspend a process if possible; give terminal to its superior.  */
void sys_suspend_process(int process)
{
        /* I don't doubt that it is possible to suspend processes on
         * VMS machines or thost that use USG_JOBCTRL,
         * but I don't know how to do it, so...
         */
#if defined (SIGTSTP)
        kill(process, SIGTSTP);
#endif
}
\f
/* Given FD, obtain pty buffer size. When no luck, a good guess is made,
   so that the function works even when fd is not a pty. */

int get_pty_max_bytes(int fd)
{
        /* DEC OSF 4.0 fpathconf returns 255, but xemacs hangs on long shell
           input lines if we return 253.  252 is OK!.  So let's leave a bit
           of slack for the newline that xemacs will insert, and for those
           inevitable vendor off-by-one-or-two-or-three bugs. */
#define MAX_CANON_SLACK 10
#define SAFE_MAX_CANON (127 - MAX_CANON_SLACK)
#if defined (HAVE_FPATHCONF) && defined (_PC_MAX_CANON)
        {
                int max_canon = fpathconf(fd, _PC_MAX_CANON);
#ifdef __hpux__
                /* HP-UX 10.20 fpathconf returns 768, but this results in
                   truncated input lines, while 255 works. */
                if (max_canon > 255)
                        max_canon = 255;
#endif
                return (max_canon < 0 ? SAFE_MAX_CANON :
                        max_canon >
                        SAFE_MAX_CANON ? max_canon -
                        MAX_CANON_SLACK : max_canon);
        }
#elif defined (_POSIX_MAX_CANON)
        return (_POSIX_MAX_CANON > SAFE_MAX_CANON ?
                _POSIX_MAX_CANON - MAX_CANON_SLACK : _POSIX_MAX_CANON);
#else
        return SAFE_MAX_CANON;
#endif
}

/* Figure out the eof character for the FD. */

Bufbyte get_eof_char(int fd)
{
        const Bufbyte ctrl_d = (Bufbyte) '\004';

        if (!isatty(fd))
                return ctrl_d;
#ifdef HAVE_TERMIOS
        {
                struct termios t;
                tcgetattr(fd, &t);
#if 0
                /* What is the following line designed to do??? -mrb */
                if (strlen((const char *)t.c_cc) < (unsigned int)(VEOF + 1))
                        return ctrl_d;
                else
                        return (Bufbyte) t.c_cc[VEOF];
#endif
                return t.c_cc[VEOF] ==
                    _POSIX_VDISABLE ? ctrl_d : (Bufbyte) t.c_cc[VEOF];
        }
#else                           /* ! HAVE_TERMIOS */
        /* On Berkeley descendants, the following IOCTL's retrieve the
           current control characters.  */
#if defined (TIOCGETC)
        {
                struct tchars c;
                ioctl(fd, TIOCGETC, &c);
                return (Bufbyte) c.t_eofc;
        }
#else                           /* ! defined (TIOCGLTC) && defined (TIOCGETC) */
        /* On SYSV descendants, the TCGETA ioctl retrieves the current control
           characters.  */
#ifdef TCGETA
        {
                struct termio t;
                ioctl(fd, TCGETA, &t);
                if (strlen((const char *)t.c_cc) < (unsigned int)(VINTR + 1))
                        return ctrl_d;
                else
                        return (Bufbyte) t.c_cc[VINTR];
        }
#else                           /* ! defined (TCGETA) */
        /* Rather than complain, we'll just guess ^D, which is what
         * earlier emacsen always used. */
        return ctrl_d;
#endif                          /* ! defined (TCGETA) */
#endif                          /* ! defined (TIOCGETC) */
#endif                          /* ! defined (HAVE_TERMIOS) */
}

/* Set the logical window size associated with descriptor FD
   to HEIGHT and WIDTH.  This is used mainly with ptys.  */

int set_window_size(int fd, int height, int width)
{
#ifdef TIOCSWINSZ

        /* BSD-style.  */
        struct winsize size;
        size.ws_row = height;
        size.ws_col = width;

        if (ioctl(fd, TIOCSWINSZ, &size) == -1)
                return 0;       /* error */
        else
                return 1;

#elif defined (TIOCSSIZE)

        /* SunOS - style.  */
        struct ttysize size;
        size.ts_lines = height;
        size.ts_cols = width;

        if (ioctl(fd, TIOCGSIZE, &size) == -1)
                return 0;
        else
                return 1;
#else
        return -1;
#endif
}

#ifdef HAVE_PTYS

/* Set up the proper status flags for use of a pty.  */

void setup_pty(int fd)
{
        /* I'm told that TIOCREMOTE does not mean control chars
           "can't be sent" but rather that they don't have
           input-editing or signaling effects.
           That should be good, because we have other ways
           to do those things in Emacs.
           However, telnet mode seems not to work on 4.2.
           So TIOCREMOTE is turned off now. */

        /* Under hp-ux, if TIOCREMOTE is turned on, some calls
           will hang.  In particular, the "timeout" feature (which
           causes a read to return if there is no data available)
           does this.  Also it is known that telnet mode will hang
           in such a way that Emacs must be stopped (perhaps this
           is the same problem).

           If TIOCREMOTE is turned off, then there is a bug in
           hp-ux which sometimes loses data.  Apparently the
           code which blocks the master process when the internal
           buffer fills up does not work.  Other than this,
           though, everything else seems to work fine.

           Since the latter lossage is more benign, we may as well
           lose that way.  -- cph */
#if defined (FIONBIO) && defined (SYSV_PTYS)
        {
                int on = 1;
                ioctl(fd, FIONBIO, &on);
        }
#endif
#ifdef IBMRTAIX
        /* On AIX, the parent gets SIGHUP when a pty attached child dies.  So, we */
        /* ignore SIGHUP once we've started a child on a pty.  Note that this may */
        /* cause EMACS not to die when it should, i.e., when its own controlling  */
        /* tty goes away.  I've complained to the AIX developers, and they may    */
        /* change this behavior, but I'm not going to hold my breath.             */
        signal(SIGHUP, SIG_IGN);
#endif
#ifdef TIOCPKT
        /* In some systems (Linux through 2.0.0, at least), packet mode doesn't
           get cleared when a pty is closed, so we need to clear it here.
           Linux pre2.0.13 contained an attempted fix for this (from Ted Ts'o,
           tytso@mit.edu), but apparently it messed up rlogind and telnetd, so he
           removed the fix in pre2.0.14.     - dkindred@cs.cmu.edu
         */
        {
                int off = 0;
                ioctl(fd, TIOCPKT, (char *)&off);
        }
#endif
}
#endif                          /* HAVE_PTYS */
\f
/************************************************************************/
/*                            TTY control                               */
/************************************************************************/

/* ------------------------------------------------------ */
/*                     get baud rate                      */
/* ------------------------------------------------------ */

/* It really makes more sense for the baud-rate to be console-specific
   and not device-specific, but it's (at least potentially) used for output
   decisions. */

void init_baud_rate(struct device *d)
{
        struct console *con = XCONSOLE(DEVICE_CONSOLE(d));
        if (DEVICE_WIN_P(d) || DEVICE_STREAM_P(d)) {
                DEVICE_BAUD_RATE(d) = 38400;
                return;
        }
#ifdef HAVE_TTY
        assert(DEVICE_TTY_P(d));
        {
                int input_fd = CONSOLE_TTY_DATA(con)->infd;
#if defined (HAVE_TERMIOS)
                struct termios sg;

                sg.c_cflag = B9600;
                tcgetattr(input_fd, &sg);
                DEVICE_TTY_DATA(d)->ospeed = cfgetospeed(&sg);
# if defined (USE_GETOBAUD) && defined (getobaud)
                /* m88k-motorola-sysv3 needs this (ghazi@noc.rutgers.edu) 9/1/94. */
                if (DEVICE_TTY_DATA(d)->ospeed == 0)
                        DEVICE_TTY_DATA(d)->ospeed = getobaud(sg.c_cflag);
# endif
#elif defined (HAVE_TERMIO)
                struct termio sg;

                sg.c_cflag = B9600;
# ifdef HAVE_TCATTR
                tcgetattr(input_fd, &sg);
# else
                ioctl(input_fd, TCGETA, &sg);
# endif
                DEVICE_TTY_DATA(d)->ospeed = sg.c_cflag & CBAUD;
#else                           /* neither TERMIOS nor TERMIO */
                struct sgttyb sg;

                sg.sg_ospeed = B9600;
                if (ioctl(input_fd, TIOCGETP, &sg) < 0)
                        abort();
                DEVICE_TTY_DATA(d)->ospeed = sg.sg_ospeed;
#endif
        }

        DEVICE_BAUD_RATE(d) =
            (DEVICE_TTY_DATA(d)->ospeed < countof(baud_convert)
             ? baud_convert[DEVICE_TTY_DATA(d)->ospeed]
             : 9600);

        if (DEVICE_BAUD_RATE(d) == 0)
                DEVICE_BAUD_RATE(d) = 1200;
#endif                          /* HAVE_TTY */
}
\f
/* ------------------------------------------------------ */
/*                       SIGIO control                    */
/* ------------------------------------------------------ */

#if defined(SIGIO) && !defined(BROKEN_SIGIO)

static void init_sigio_on_device(struct device *d)
{
        int filedesc = DEVICE_INFD(d);

#if defined (FIOSSAIOOWN)
        {                       /* HPUX stuff */
                int owner = getpid();
                int ioctl_status;
                if (DEVICE_TTY_P(d)) {
                        ioctl_status = ioctl(filedesc, FIOGSAIOOWN,
                                             &DEVICE_OLD_FCNTL_OWNER(d));
                        ioctl_status = ioctl(filedesc, FIOSSAIOOWN, &owner);
                }
#ifdef HAVE_WINDOW_SYSTEM
                else if (!DEVICE_STREAM_P(d)) {
                        ioctl_status = ioctl(filedesc, SIOCGPGRP,
                                             &DEVICE_OLD_FCNTL_OWNER(d));
                        ioctl_status = ioctl(filedesc, SIOCSPGRP, &owner);
                }
#endif
        }
#elif defined (F_SETOWN) && !defined (F_SETOWN_BUG)
        DEVICE_OLD_FCNTL_OWNER(d) = fcntl(filedesc, F_GETOWN, 0);
# ifdef F_SETOWN_SOCK_NEG
        /* stdin is a socket here */
        fcntl(filedesc, F_SETOWN, -getpid());
# else
        fcntl(filedesc, F_SETOWN, getpid());
# endif
#endif
}

static void reset_sigio_on_device(struct device *d)
{
        int filedesc = DEVICE_INFD(d);

#if defined (FIOSSAIOOWN)
        {                       /* HPUX stuff */
                int ioctl_status;
                if (DEVICE_TTY_P(d)) {
                        ioctl_status = ioctl(filedesc, FIOSSAIOOWN,
                                             &DEVICE_OLD_FCNTL_OWNER(d));
                }
#ifdef HAVE_WINDOW_SYSTEM
                else if (!DEVICE_STREAM_P(d)) {
                        ioctl_status = ioctl(filedesc, SIOCSPGRP,
                                             &DEVICE_OLD_FCNTL_OWNER(d));
                }
#endif
        }
#elif defined (F_SETOWN) && !defined (F_SETOWN_BUG)
        fcntl(filedesc, F_SETOWN, DEVICE_OLD_FCNTL_OWNER(d));
#endif
}

static void request_sigio_on_device(struct device *d)
{
        int filedesc = DEVICE_INFD(d);

#if defined (I_SETSIG) && !defined(HPUX10) && !defined(LINUX)
        {
                int events = 0;
                ioctl(filedesc, I_GETSIG, &events);
                ioctl(filedesc, I_SETSIG, events | S_INPUT);
        }
#elif defined (FASYNC)
        fcntl(filedesc, F_SETFL, fcntl(filedesc, F_GETFL, 0) | FASYNC);
#elif defined (FIOSSAIOSTAT)
        {
                /* DG: Changed for HP-UX. HP-UX uses different IOCTLs for
                   sockets and other devices for some bizarre reason. We guess
                   that an X device is a socket, and tty devices aren't. We then
                   use the following crud to do the appropriate thing. */
                int on = 1;
                int ioctl_status;       /* ####DG: check if IOCTL succeeds here. */

                if (DEVICE_TTY_P(d)) {
                        ioctl_status = ioctl(filedesc, FIOSSAIOSTAT, &on);
                }
#ifdef HAVE_WINDOW_SYSTEM
                else if (!DEVICE_STREAM_P(d)) {
                        ioctl_status = ioctl(filedesc, FIOASYNC, &on);
                }
#endif
        }
#elif defined (FIOASYNC)
        {
                int on = 1;
                ioctl(filedesc, FIOASYNC, &on);
        }
#endif

#if defined (_CX_UX)            /* #### Is this crap necessary? */
        EMACS_UNBLOCK_SIGNAL(SIGIO);
#endif
}

static void unrequest_sigio_on_device(struct device *d)
{
        int filedesc = DEVICE_INFD(d);

#if defined (I_SETSIG) && !defined(HPUX10)
        {
                int events = 0;
                ioctl(filedesc, I_GETSIG, &events);
                ioctl(filedesc, I_SETSIG, events & ~S_INPUT);
        }
#elif defined (FASYNC)
        fcntl(filedesc, F_SETFL, fcntl(filedesc, F_GETFL, 0) & ~FASYNC);
#elif defined (FIOSSAIOSTAT)
        {
                /* DG: Changed for HP-UX. HP-UX uses different IOCTLs for
                   sockets and other devices for some bizarre reason. We guess
                   that an X device is a socket, and tty devices aren't. We then
                   use the following crud to do the appropriate thing. */

                int off = 0;
                int ioctl_status;

                /* See comment for request_sigio_on_device */

                if (DEVICE_TTY_P(d)) {
                        ioctl_status = ioctl(filedesc, FIOSSAIOSTAT, &off);
                } else {
                        ioctl_status = ioctl(filedesc, FIOASYNC, &off);
                }
        }
#elif defined (FIOASYNC)
        {
                int off = 0;
                ioctl(filedesc, FIOASYNC, &off);
        }
#endif
}

void request_sigio(void)
{
        Lisp_Object devcons, concons;

        DEVICE_LOOP_NO_BREAK(devcons, concons) {
                struct device *d;

                d = XDEVICE(XCAR(devcons));

                if (!DEVICE_STREAM_P(d))
                        request_sigio_on_device(d);
        }
}

void unrequest_sigio(void)
{
        Lisp_Object devcons, concons;

        DEVICE_LOOP_NO_BREAK(devcons, concons) {
                struct device *d;

                d = XDEVICE(XCAR(devcons));

                if (!DEVICE_STREAM_P(d))
                        unrequest_sigio_on_device(d);
        }
}

#endif                          /* SIGIO */
\f
/* ------------------------------------------------------ */
/*             Changing Emacs's process group             */
/* ------------------------------------------------------ */

/* Saving and restoring the process group of Emacs's terminal.  */

/* On some systems, apparently (?!) Emacs must be in its own process
   group in order to receive SIGIO correctly.  On other systems
   (e.g. Solaris), it's not required and doing it makes things
   get fucked up.  So, we only do it when
   SIGIO_REQUIRES_SEPARATE_PROCESS_GROUP is defined.  Basically,
   this is only required for BSD 4.2 systems. (Actually, I bet
   we don't have to do this at all -- those systems also
   required interrupt input, which we don't support.)

   If Emacs was in its own process group (i.e. inherited_pgroup ==
   getpid ()), then we know we're running under a shell with job
   control (Emacs would never be run as part of a pipeline).
   Everything is fine.

   If Emacs was not in its own process group, then we know we're
   running under a shell (or a caller) that doesn't know how to
   separate itself from Emacs (like sh).  Emacs must be in its own
   process group in order to receive SIGIO correctly.  In this
   situation, we put ourselves in our own pgroup, forcibly set the
   tty's pgroup to our pgroup, and make sure to restore and reinstate
   the tty's pgroup just like any other terminal setting.  If
   inherited_group was not the tty's pgroup, then we'll get a
   SIGTTmumble when we try to change the tty's pgroup, and a CONT if
   it goes foreground in the future, which is what should happen.  */

#ifdef SIGIO_REQUIRES_SEPARATE_PROCESS_GROUP

static pid_t inherited_pgroup;
static pid_t inherited_tty_pgroup;

#endif

void munge_tty_process_group(void)
{
#ifdef SIGIO_REQUIRES_SEPARATE_PROCESS_GROUP
        if (noninteractive)
                return;

        /* Only do this munging if we have a device on the controlling
           terminal.  See the large comment below. */

        if (CONSOLEP(Vcontrolling_terminal) &&
            CONSOLE_LIVE_P(XCONSOLE(Vcontrolling_terminal))) {
                int fd = open("/dev/tty", O_RDWR, 0);
                pid_t me = getpid();
                EMACS_BLOCK_SIGNAL(SIGTTOU);
                EMACS_SET_TTY_PROCESS_GROUP(fd, &me);
                EMACS_UNBLOCK_SIGNAL(SIGTTOU);
                close(fd);
        }
#endif
}

/* Split off the foreground process group to Emacs alone.
   When we are in the foreground, but not started in our own process
   group, redirect the TTY to point to our own process group.  We need
   to be in our own process group to receive SIGIO properly.  */
static void munge_process_groups(void)
{
#ifdef SIGIO_REQUIRES_SEPARATE_PROCESS_GROUP
        if (noninteractive)
                return;

        EMACS_SEPARATE_PROCESS_GROUP();

        munge_tty_process_group();
#endif
}

void unmunge_tty_process_group(void)
{
#ifdef SIGIO_REQUIRES_SEPARATE_PROCESS_GROUP
        {
                int fd = open("/dev/tty", O_RDWR, 0);
                EMACS_BLOCK_SIGNAL(SIGTTOU);
                EMACS_SET_TTY_PROCESS_GROUP(fd, &inherited_tty_pgroup);
                EMACS_UNBLOCK_SIGNAL(SIGTTOU);
                close(fd);
        }
#endif
}

/* Set the tty to our original foreground group.
   Also restore the original process group (put us back into sh's
   process group), so that ^Z will suspend both us and sh. */
static void unmunge_process_groups(void)
{
#ifdef SIGIO_REQUIRES_SEPARATE_PROCESS_GROUP
        if (noninteractive)
                return;

        unmunge_tty_process_group();

        EMACS_SET_PROCESS_GROUP(inherited_pgroup);
#endif
}

/* According to some old wisdom, we need to be in a separate process
   group for SIGIO to work correctly (at least on some systems ...).
   So go ahead and put ourselves into our own process group.  This
   will fail if we're already in our own process group, but who cares.
   Also record whether we were in our own process group. (In general,
   we will already be in our own process group if we were started from
   a job-control shell like csh, but not if we were started from sh).

   If we succeeded in changing our process group, then we will no
   longer be in the foreground process group of our controlling
   terminal.  Therefore, if we have a console open onto this terminal,
   we have to change the controlling terminal's foreground process
   group (otherwise we will get stopped with a SIGTTIN signal when
   attempting to read from the terminal).  It's important,
   however, that we do this *only* when we have a console open onto
   the terminal.  It's a decidedly bad idea to do so otherwise,
   especially if XEmacs was started from the background. */

void init_process_group(void)
{
#ifdef SIGIO_REQUIRES_SEPARATE_PROCESS_GROUP
        if (!noninteractive) {
                int fd = open("/dev/tty", O_RDWR, 0);
                inherited_pgroup = EMACS_GET_PROCESS_GROUP();
                EMACS_GET_TTY_PROCESS_GROUP(fd, &inherited_tty_pgroup);
                close(fd);
                EMACS_SEPARATE_PROCESS_GROUP();
        }
#endif
}

void disconnect_controlling_terminal(void)
{
#  ifdef HAVE_SETSID
        /* Controlling terminals are attached to a session.
           Create a new session for us; it will have no controlling
           terminal.  This also, of course, puts us in our own
           process group. */
        setsid();
#  else
        /* Put us in our own process group. */
        EMACS_SEPARATE_PROCESS_GROUP();
#    if defined (TIOCNOTTY)
        /* This is the older way of disconnecting the controlling
           terminal, on 4.3 BSD.  We must open /dev/tty; using
           filedesc 0 is not sufficient because it could be
           something else (e.g. our stdin was redirected to
           another terminal).
         */
        {
                int j = open("/dev/tty", O_RDWR, 0);
                ioctl(j, TIOCNOTTY, 0);
                close(j);
        }
#    endif                      /* TIOCNOTTY */
        /*
           On systems without TIOCNOTTY and without
           setsid(), we don't need to do anything more to
           disconnect our controlling terminal.  Here is
           what the man page for termio(7) from a SYSV 3.2
           system says:

           "The first terminal file opened by the process group leader
           of a terminal file not already associated with a process
           group becomes the control terminal for that process group.
           The control terminal plays a special role in handling quit
           and interrupt signals, as discussed below.  The control
           terminal is inherited by a child process during a fork(2).
           A process can break this association by changing its process
           group using setpgrp(2)."

         */
#  endif                        /* not HAVE_SETSID */
}
\f
/* ------------------------------------------------------ */
/*        Getting and setting emacs_tty structures        */
/* ------------------------------------------------------ */

/* It's wrong to encase these into #ifdef HAVE_TTY because we need
   them for child TTY processes.  */
/* However, this does break NT support while we don't do child TTY processes */

/* Set *TC to the parameters associated with the terminal FD.
   Return zero if all's well, or -1 if we ran into an error we
   couldn't deal with.  */
int emacs_get_tty(int fd, struct emacs_tty *settings)
{
        /* Retrieve the primary parameters - baud rate, character size, etcetera.  */
#ifdef HAVE_TCATTR
        /* We have those nifty POSIX tcmumbleattr functions.  */
        if (tcgetattr(fd, &settings->main) < 0)
                return -1;

#elif defined HAVE_TERMIO
        /* The SYSV-style interface?  */
        if (ioctl(fd, TCGETA, &settings->main) < 0)
                return -1;

#else
        /* I give up - I hope you have the BSD ioctls.  */
        if (ioctl(fd, TIOCGETP, &settings->main) < 0)
                return -1;
#endif                          /* HAVE_TCATTR */

        /* Suivant - Do we have to get struct ltchars data?  */
#ifdef HAVE_LTCHARS
        if (ioctl(fd, TIOCGLTC, &settings->ltchars) < 0)
                return -1;
#endif

        /* How about a struct tchars and a wordful of lmode bits?  */
#ifdef HAVE_TCHARS
        if (ioctl(fd, TIOCGETC, &settings->tchars) < 0
            || ioctl(fd, TIOCLGET, &settings->lmode) < 0)
                return -1;
#endif

        /* We have survived the tempest.  */
        return 0;
}

/* Set the parameters of the tty on FD according to the contents of
   *SETTINGS.  If FLUSHP is non-zero, we discard input.
   Return 0 if all went well, and -1 if anything failed.
   #### All current callers use FLUSHP == 0. */

int emacs_set_tty(int fd, struct emacs_tty *settings, int flushp)
{
        /* Set the primary parameters - baud rate, character size, etcetera.  */
#ifdef HAVE_TCATTR
        int i;
        /* We have those nifty POSIX tcmumbleattr functions.
           William J. Smith <wjs@wiis.wang.com> writes:
           "POSIX 1003.1 defines tcsetattr() to return success if it was
           able to perform any of the requested actions, even if some
           of the requested actions could not be performed.
           We must read settings back to ensure tty setup properly.
           AIX requires this to keep tty from hanging occasionally."  */
        /* This makes sure that we don't loop indefinitely in here.  */
        for (i = 0; i < 10; i++)
                if (tcsetattr
                    (fd, flushp ? TCSAFLUSH : TCSADRAIN, &settings->main) < 0) {
                        if (errno == EINTR)
                                continue;
                        else
                                return -1;
                } else {
                        struct termios new;

                        /* Get the current settings, and see if they're what we asked for.  */
                        tcgetattr(fd, &new);
                        /* We cannot use memcmp on the whole structure here because under
                         * aix386 the termios structure has some reserved field that may
                         * not be filled in.
                         */
                        if (new.c_iflag == settings->main.c_iflag
                            && new.c_oflag == settings->main.c_oflag
                            && new.c_cflag == settings->main.c_cflag
                            && new.c_lflag == settings->main.c_lflag
                            && memcmp(new.c_cc, settings->main.c_cc, NCCS) == 0)
                                break;
                        else
                                continue;
                }
#elif defined HAVE_TERMIO
        /* The SYSV-style interface?  */
        if (ioctl(fd, flushp ? TCSETAF : TCSETAW, &settings->main) < 0)
                return -1;

#else
        /* I give up - I hope you have the BSD ioctls.  */
        if (ioctl(fd, (flushp) ? TIOCSETP : TIOCSETN, &settings->main) < 0)
                return -1;
#endif                          /* HAVE_TCATTR */

        /* Suivant - Do we have to get struct ltchars data?  */
#ifdef HAVE_LTCHARS
        if (ioctl(fd, TIOCSLTC, &settings->ltchars) < 0)
                return -1;
#endif

        /* How about a struct tchars and a wordful of lmode bits?  */
#ifdef HAVE_TCHARS
        if (ioctl(fd, TIOCSETC, &settings->tchars) < 0
            || ioctl(fd, TIOCLSET, &settings->lmode) < 0)
                return -1;
#endif

        /* We have survived the tempest.  */
        return 0;
}

\f
/* ------------------------------------------------------ */
/*                 Initializing a device                  */
/* ------------------------------------------------------ */

#ifdef HAVE_TTY

/* This may also be defined in stdio,
   but if so, this does no harm,
   and using the same name avoids wasting the other one's space.  */

#if ((defined(USG) || defined(DGUX)) && !defined(__STDC__))
char _sobuf[BUFSIZ + 8];
#elif (defined(USG) && !defined(LINUX) && !defined(_SCO_DS)) || defined(IRIX5)
extern unsigned char _sobuf[BUFSIZ + 8];
#else
char _sobuf[BUFSIZ];
#endif

#if defined (TIOCGLTC) && defined (HAVE_LTCHARS)        /* HAVE_LTCHARS */
static struct ltchars new_ltchars = { -1, -1, -1, -1, -1, -1 };
#endif
#ifdef TIOCGETC                 /* HAVE_TCHARS */
#ifdef HAVE_TCHARS
static struct tchars new_tchars = { -1, -1, -1, -1, -1, -1 };
#endif
#endif

static void tty_init_sys_modes_on_device(struct device *d)
{
        struct emacs_tty tty;
        int input_fd, output_fd;
        struct console *con = XCONSOLE(DEVICE_CONSOLE(d));

        input_fd = CONSOLE_TTY_DATA(con)->infd;
        output_fd = CONSOLE_TTY_DATA(con)->outfd;

        emacs_get_tty(input_fd, &CONSOLE_TTY_DATA(con)->old_tty);
        tty = CONSOLE_TTY_DATA(con)->old_tty;

        con->tty_erase_char = Qnil;

#if defined (HAVE_TERMIO) || defined (HAVE_TERMIOS)
        /* after all those years... */
        con->tty_erase_char = make_char(tty.main.c_cc[VERASE]);
#ifdef DGUX
        /* This allows meta to be sent on 8th bit.  */
        tty.main.c_iflag &= ~INPCK;     /* don't check input for parity */
#endif
        tty.main.c_iflag |= (IGNBRK);   /* Ignore break condition */
        tty.main.c_iflag &= ~ICRNL;     /* Disable map of CR to NL on input */
#ifdef ISTRIP
        tty.main.c_iflag &= ~ISTRIP;    /* don't strip 8th bit on input */
#endif
        tty.main.c_lflag &= ~ECHO;      /* Disable echo */
        tty.main.c_lflag &= ~ICANON;    /* Disable erase/kill processing */
#ifdef IEXTEN
        tty.main.c_lflag &= ~IEXTEN;    /* Disable other editing characters.  */
#endif
        tty.main.c_lflag |= ISIG;       /* Enable signals */
        if (TTY_FLAGS(con).flow_control) {
                tty.main.c_iflag |= IXON;       /* Enable start/stop output control */
#ifdef IXANY
                tty.main.c_iflag &= ~IXANY;
#endif                          /* IXANY */
        } else
                tty.main.c_iflag &= ~IXON;      /* Disable start/stop output control */
        tty.main.c_oflag &= ~ONLCR;     /* Disable map of NL to CR-NL
                                           on output */
        tty.main.c_oflag &= ~TAB3;      /* Disable tab expansion */
#ifdef CS8
        if (TTY_FLAGS(con).meta_key) {
                tty.main.c_cflag |= CS8;        /* allow 8th bit on input */
                tty.main.c_cflag &= ~PARENB;    /* Don't check parity */
        }
#endif
        if (CONSOLE_TTY_DATA(con)->controlling_terminal) {
                tty.main.c_cc[VINTR] = CONSOLE_QUIT_CHAR(con);  /* C-g (usually) gives SIGINT */
                /* Set up C-g for both SIGQUIT and SIGINT.
                   We don't know which we will get, but we handle both alike
                   so which one it really gives us does not matter.  */
                tty.main.c_cc[VQUIT] = CONSOLE_QUIT_CHAR(con);
        } else {
                tty.main.c_cc[VINTR] = _POSIX_VDISABLE;
                tty.main.c_cc[VQUIT] = _POSIX_VDISABLE;
        }
        tty.main.c_cc[VMIN] = 1;        /* Input should wait for at
                                           least 1 char */
        tty.main.c_cc[VTIME] = 0;       /* no matter how long that takes.  */
#ifdef VSWTCH
        tty.main.c_cc[VSWTCH] = _POSIX_VDISABLE;        /* Turn off shell layering use
                                                           of C-z */
#endif                          /* VSWTCH */
        /* There was some conditionalizing here on (mips or TCATTR), but
           I think that's wrong.  There was one report of C-y (DSUSP) not being
           disabled on HP9000s700 systems, and this might fix it. */
#ifdef VSUSP
        tty.main.c_cc[VSUSP] = _POSIX_VDISABLE; /* Turn off mips handling of C-z. */
#endif                          /* VSUSP */
#ifdef V_DSUSP
        tty.main.c_cc[V_DSUSP] = _POSIX_VDISABLE;       /* Turn off mips handling of C-y. */
#endif                          /* V_DSUSP */
#ifdef VDSUSP                   /* Some systems have VDSUSP, some have V_DSUSP.  */
        tty.main.c_cc[VDSUSP] = _POSIX_VDISABLE;
#endif                          /* VDSUSP */
#ifdef VLNEXT
        tty.main.c_cc[VLNEXT] = _POSIX_VDISABLE;
#endif                          /* VLNEXT */
#ifdef VREPRINT
        tty.main.c_cc[VREPRINT] = _POSIX_VDISABLE;
#endif                          /* VREPRINT */
#ifdef VWERASE
        tty.main.c_cc[VWERASE] = _POSIX_VDISABLE;
#endif                          /* VWERASE */
#ifdef VDISCARD
        tty.main.c_cc[VDISCARD] = _POSIX_VDISABLE;
#endif                          /* VDISCARD */
#ifdef VSTART
        tty.main.c_cc[VSTART] = _POSIX_VDISABLE;
#endif                          /* VSTART */
#ifdef VSTRT
        tty.main.c_cc[VSTRT] = _POSIX_VDISABLE; /* called VSTRT on some systems */
#endif                          /* VSTART */
#ifdef VSTOP
        tty.main.c_cc[VSTOP] = _POSIX_VDISABLE;
#endif                          /* VSTOP */
#ifdef SET_LINE_DISCIPLINE
        /* Need to explicitly request TERMIODISC line discipline or
           Ultrix's termios does not work correctly.  */
        tty.main.c_line = SET_LINE_DISCIPLINE;
#endif

#ifdef AIX
#ifndef IBMR2AIX
        /* AIX enhanced edit loses NULs, so disable it. */
        tty.main.c_line = 0;
        tty.main.c_iflag &= ~ASCEDIT;
#else
        tty.main.c_cc[VSTRT] = 255;
        tty.main.c_cc[VSTOP] = 255;
        tty.main.c_cc[VSUSP] = 255;
        tty.main.c_cc[VDSUSP] = 255;
#endif                          /* IBMR2AIX */
        /* Also, PTY overloads NUL and BREAK.
           don't ignore break, but don't signal either, so it looks like NUL.
           This really serves a purpose only if running in an XTERM window
           or via TELNET or the like, but does no harm elsewhere.  */
        tty.main.c_iflag &= ~IGNBRK;
        tty.main.c_iflag &= ~BRKINT;
#endif                          /* AIX */
#else                           /* if not HAVE_TERMIO */
        con->tty_erase_char = make_char(tty.main.sg_erase);
        tty.main.sg_flags &= ~(ECHO | CRMOD | XTABS);
        if (TTY_FLAGS(con).meta_key)
                tty.main.sg_flags |= ANYP;
        /* #### should we be using RAW mode here? */
        tty.main.sg_flags |= /* interrupt_input ? RAW : */ CBREAK;
#endif                          /* not HAVE_TERMIO */

        /* If going to use CBREAK mode, we must request C-g to interrupt
           and turn off start and stop chars, etc.  If not going to use
           CBREAK mode, do this anyway so as to turn off local flow
           control for user coming over network on 4.2; in this case,
           only t_stopc and t_startc really matter.  */
#ifndef HAVE_TERMIO
#ifdef HAVE_TCHARS
        /* Note: if not using CBREAK mode, it makes no difference how we
           set this */
        tty.tchars = new_tchars;
        tty.tchars.t_intrc = CONSOLE_QUIT_CHAR(con);
        if (TTY_FLAGS(con).flow_control) {
                tty.tchars.t_startc = '\021';
                tty.tchars.t_stopc = '\023';
        }

        tty.lmode = LDECCTQ | LLITOUT | LPASS8 | LNOFLSH |
            CONSOLE_TTY_DATA(con)->old_tty.lmode;

#if defined (ultrix) || defined (__bsdi__)
        /* Under Ultrix 4.2a, leaving this out doesn't seem to hurt
           anything, and leaving it in breaks the meta key.  Go figure.  */
        /* Turning off ONLCR is enough under BSD/386.  Leave the general
           output post-processing flag alone since for some reason it
           doesn't get reset after XEmacs goes away. */
        tty.lmode &= ~LLITOUT;
#endif

#endif                          /* HAVE_TCHARS */
#endif                          /* not HAVE_TERMIO */

#ifdef HAVE_LTCHARS
        tty.ltchars = new_ltchars;
#endif                          /* HAVE_LTCHARS */

        emacs_set_tty(input_fd, &tty, 0);

        /* This code added to insure that, if flow-control is not to be used,
           we have an unlocked terminal at the start. */

#ifdef TCXONC
        if (!TTY_FLAGS(con).flow_control)
                ioctl(input_fd, TCXONC, 1);
#endif
#ifdef TIOCSTART
        if (!TTY_FLAGS(con).flow_control)
                ioctl(input_fd, TIOCSTART, 0);
#endif

#if defined (HAVE_TERMIOS) || defined (HPUX9)
#ifdef TCOON
        if (!TTY_FLAGS(con).flow_control)
                tcflow(input_fd, TCOON);
#endif
#endif
#ifdef AIXHFT
        hft_init(con);
#ifdef IBMR2AIX
        {
                /* IBM's HFT device usually thinks a ^J should be LF/CR.
                   We need it to be only LF.  This is the way that is
                   done. */
                struct termio tty;

                if (ioctl(output_fd, HFTGETID, &tty) != -1)
                        write(output_fd, "\033[20l", 5);
        }
#endif
#endif

#if 0                           /* We do our own buffering with lstreams. */
#ifdef _IOFBF
        /* This symbol is defined on recent USG systems.
           Someone says without this call USG won't really buffer the file
           even with a call to setbuf. */
        setvbuf(CONSOLE_TTY_DATA(con)->outfd, (char *)_sobuf, _IOFBF,
                sizeof _sobuf);
#else
        setbuf(CONSOLE_TTY_DATA(con)->outfd, (char *)_sobuf);
#endif
#endif
        set_tty_modes(con);
}

#endif                          /* HAVE_TTY */

void init_one_device(struct device *d)
{
#ifdef HAVE_TTY
        if (DEVICE_TTY_P(d))
                tty_init_sys_modes_on_device(d);
#endif
#if defined(SIGIO) && !defined(BROKEN_SIGIO)
        if (!DEVICE_STREAM_P(d)) {
                init_sigio_on_device(d);
                request_sigio_on_device(d);
        }
#endif
}

void init_one_console(struct console *con)
{
        Lisp_Object devcons;

        CONSOLE_DEVICE_LOOP(devcons, con) {
                struct device *d = XDEVICE(XCAR(devcons));

                init_one_device(d);
        }
}

void reinit_initial_console(void)
{
        munge_process_groups();
        if (CONSOLEP(Vcontrolling_terminal) &&
            CONSOLE_LIVE_P(XCONSOLE(Vcontrolling_terminal)))
                init_one_console(XCONSOLE(Vcontrolling_terminal));
}
\f
/* ------------------------------------------------------ */
/*                   Other TTY functions                  */
/* ------------------------------------------------------ */

#ifdef HAVE_TTY

#if 0                           /* not currently used */

/* Return nonzero if safe to use tabs in output.
   At the time this is called, init_sys_modes has not been done yet.  */

int tabs_safe_p(struct device *d)
{
#ifdef HAVE_TTY
        if (DEVICE_TTY_P(d)) {
                struct emacs_tty tty;

                emacs_get_tty(DEVICE_INFD(d), &tty);
                return EMACS_TTY_TABS_OK(&tty);
        }
#endif
        return 1;
}

#endif                          /* 0 */

/* Get terminal size from system.
   Store number of lines into *heightp and width into *widthp.
   If zero or a negative number is stored, the value is not valid.  */

void get_tty_device_size(struct device *d, int *widthp, int *heightp)
{
        int input_fd = DEVICE_INFD(d);

        assert(DEVICE_TTY_P(d));

#ifdef TIOCGWINSZ
        {
                /* BSD-style.  */
                struct winsize size;

                if (ioctl(input_fd, TIOCGWINSZ, &size) == -1)
                        *widthp = *heightp = 0;
                else {
                        *widthp = size.ws_col;
                        *heightp = size.ws_row;
                }
        }
#elif defined TIOCGSIZE
        {
                /* SunOS - style.  */
                struct ttysize size;

                if (ioctl(input_fd, TIOCGSIZE, &size) == -1)
                        *widthp = *heightp = 0;
                else {
                        *widthp = size.ts_cols;
                        *heightp = size.ts_lines;
                }
        }
#else                           /* system doesn't know size */

        *widthp = 0;
        *heightp = 0;

#endif                          /* not !TIOCGWINSZ */
}

#endif                          /* HAVE_TTY */
\f
/* ------------------------------------------------------ */
/*                   Is device 8 bit ?                    */
/* ------------------------------------------------------ */

#ifdef HAVE_TTY

int eight_bit_tty(struct device *d)
{
        struct emacs_tty s;
        int input_fd;
        int eight_bit = 0;

        assert(DEVICE_TTY_P(d));
        input_fd = DEVICE_INFD(d);

        emacs_get_tty(input_fd, &s);

#if defined (HAVE_TERMIO) || defined (HAVE_TERMIOS)
        eight_bit = (s.main.c_cflag & CSIZE) == CS8;
#else
        eight_bit = 0;          /* I don't know how to do it */
#endif
        return eight_bit;
}

#endif                          /* HAVE_TTY */
\f
/* ------------------------------------------------------ */
/*                   Resetting a device                   */
/* ------------------------------------------------------ */

#ifdef HAVE_TTY

/* Prepare the terminal for exiting Emacs; move the cursor to the
   bottom of the frame, turn off interrupt-driven I/O, etc.  */
static void tty_reset_sys_modes_on_device(struct device *d)
{
        int input_fd, output_fd;
        struct console *con = XCONSOLE(DEVICE_CONSOLE(d));

        input_fd = CONSOLE_TTY_DATA(con)->infd;
        output_fd = CONSOLE_TTY_DATA(con)->outfd;

#if defined (IBMR2AIX) && defined (AIXHFT)
        {
                /* HFT consoles normally use ^J as a LF/CR.  We forced it to
                   do the LF only.  Now, we need to reset it. */
                struct termio tty;

                if (ioctl(output_fd, HFTGETID, &tty) != -1)
                        write(output_fd, "\033[20h", 5);
        }
#endif

        tty_redisplay_shutdown(con);
        /* reset_tty_modes() flushes the connection at its end. */
        reset_tty_modes(con);

#if defined (BSD)
        /* Avoid possible loss of output when changing terminal modes.  */
        fsync(output_fd);
#endif

        while (emacs_set_tty(input_fd, &CONSOLE_TTY_DATA(con)->old_tty, 0)
               < 0 && errno == EINTR) ;

#ifdef SET_LINE_DISCIPLINE
        /* Ultrix's termios *ignores* any line discipline except TERMIODISC.
           A different old line discipline is therefore not restored, yet.
           Restore the old line discipline by hand.  */
        ioctl(input_fd, TIOCSETD, &old_tty.main.c_line);
#endif

#ifdef AIXHFT
        hft_reset(con);
#endif

}

#endif                          /* HAVE_TTY */

void reset_one_device(struct device *d)
{
#ifdef HAVE_TTY
        if (DEVICE_TTY_P(d))
                tty_reset_sys_modes_on_device(d);
        else
#endif
        if (DEVICE_STREAM_P(d))
                fflush(CONSOLE_STREAM_DATA(XCONSOLE(DEVICE_CONSOLE(d)))->out);
#if defined(SIGIO) && !defined(BROKEN_SIGIO)
        if (!DEVICE_STREAM_P(d)) {
                unrequest_sigio_on_device(d);
                reset_sigio_on_device(d);
        }
#endif
}

void reset_one_console(struct console *con)
{
        /* Note: this can be called during GC. */
        Lisp_Object devcons;

        CONSOLE_DEVICE_LOOP(devcons, con) {
                struct device *d = XDEVICE(XCAR(devcons));

                reset_one_device(d);
        }
}

void reset_all_consoles(void)
{
        /* Note: this can be called during GC. */
        Lisp_Object concons;

        CONSOLE_LOOP(concons) {
                struct console *con = XCONSOLE(XCAR(concons));

                reset_one_console(con);
        }

        unmunge_process_groups();
}

void reset_initial_console(void)
{
        if (CONSOLEP(Vcontrolling_terminal) &&
            CONSOLE_LIVE_P(XCONSOLE(Vcontrolling_terminal)))
                reset_one_console(XCONSOLE(Vcontrolling_terminal));
        unmunge_process_groups();
}
\f
/* ------------------------------------------------------ */
/*                 extra TTY stuff under AIX              */
/* ------------------------------------------------------ */

#ifdef AIXHFT

/* Called from init_sys_modes.  */
static void hft_init(struct console *con)
{
        int junk;
        int input_fd;

        assert(CONSOLE_TTY_P(con));
        input_fd = CONSOLE_TTY_DATA(con)->infd;

        /* If we're not on an HFT we shouldn't do any of this.  We determine
           if we are on an HFT by trying to get an HFT error code.  If this
           call fails, we're not on an HFT. */
#ifdef IBMR2AIX
        if (ioctl(input_fd, HFQERROR, &junk) < 0)
                return;
#else                           /* not IBMR2AIX */
        if (ioctl(input_fd, HFQEIO, 0) < 0)
                return;
#endif                          /* not IBMR2AIX */

        /* On AIX the default hft keyboard mapping uses backspace rather than delete
           as the rubout key's ASCII code.  Here this is changed.  The bug is that
           there's no way to determine the old mapping, so in reset_one_console
           we need to assume that the normal map had been present.  Of course, this
           code also doesn't help if on a terminal emulator which doesn't understand
           HFT VTD's. */
        {
                struct hfbuf buf;
                struct hfkeymap keymap;

                buf.hf_bufp = (char *)&keymap;
                buf.hf_buflen = sizeof(keymap);
                keymap.hf_nkeys = 2;
                keymap.hfkey[0].hf_kpos = 15;
                keymap.hfkey[0].hf_kstate = HFMAPCHAR | HFSHFNONE;
#ifdef IBMR2AIX
                keymap.hfkey[0].hf_keyidh = '<';
#else                           /* not IBMR2AIX */
                keymap.hfkey[0].hf_page = '<';
#endif                          /* not IBMR2AIX */
                keymap.hfkey[0].hf_char = 127;
                keymap.hfkey[1].hf_kpos = 15;
                keymap.hfkey[1].hf_kstate = HFMAPCHAR | HFSHFSHFT;
#ifdef IBMR2AIX
                keymap.hfkey[1].hf_keyidh = '<';
#else                           /* not IBMR2AIX */
                keymap.hfkey[1].hf_page = '<';
#endif                          /* not IBMR2AIX */
                keymap.hfkey[1].hf_char = 127;
                hftctl(input_fd, HFSKBD, &buf);
        }
        /* #### Should probably set a console TTY flag here. */
#if 0
        /* The HFT system on AIX doesn't optimize for scrolling, so it's really ugly
           at times. */
        line_ins_del_ok = char_ins_del_ok = 0;
#endif                          /* 0 */
}

/* Reset the rubout key to backspace. */

static void hft_reset(struct console *con)
{
        struct hfbuf buf;
        struct hfkeymap keymap;
        int junk;
        int input_fd;

        assert(CONSOLE_TTY_P(con));
        input_fd = CONSOLE_TTY_DATA(con)->infd;

#ifdef IBMR2AIX
        if (ioctl(input_fd, HFQERROR, &junk) < 0)
                return;
#else                           /* not IBMR2AIX */
        if (ioctl(input_fd, HFQEIO, 0) < 0)
                return;
#endif                          /* not IBMR2AIX */

        buf.hf_bufp = (char *)&keymap;
        buf.hf_buflen = sizeof(keymap);
        keymap.hf_nkeys = 2;
        keymap.hfkey[0].hf_kpos = 15;
        keymap.hfkey[0].hf_kstate = HFMAPCHAR | HFSHFNONE;
#ifdef IBMR2AIX
        keymap.hfkey[0].hf_keyidh = '<';
#else                           /* not IBMR2AIX */
        keymap.hfkey[0].hf_page = '<';
#endif                          /* not IBMR2AIX */
        keymap.hfkey[0].hf_char = 8;
        keymap.hfkey[1].hf_kpos = 15;
        keymap.hfkey[1].hf_kstate = HFMAPCHAR | HFSHFSHFT;
#ifdef IBMR2AIX
        keymap.hfkey[1].hf_keyidh = '<';
#else                           /* not IBMR2AIX */
        keymap.hfkey[1].hf_page = '<';
#endif                          /* not IBMR2AIX */
        keymap.hfkey[1].hf_char = 8;
        hftctl(input_fd, HFSKBD, &buf);
}

#endif                          /* AIXHFT */
\f
/************************************************************************/
/*                    limits of text/data segments                      */
/************************************************************************/

#if !defined(CANNOT_DUMP) && !defined(PDUMP)
#define NEED_STARTS
#endif

#ifndef SYSTEM_MALLOC
#ifndef NEED_STARTS
#define NEED_STARTS
#endif
#endif

#ifdef NEED_STARTS
/* Some systems that cannot dump also cannot implement these.  */

/*
 *      Return the address of the start of the text segment prior to
 *      doing an unexec.  After unexec the return value is undefined.
 *      See crt0.c for further explanation and _start.
 *
 */

#if !defined(HAVE_TEXT_START) && !defined(PDUMP)

EXTERN_C int _start(void);

char *start_of_text(void)
{
#ifdef TEXT_START
        return (char *)TEXT_START;
#else
        return (char *)_start;
#endif                          /* TEXT_START */
}
#endif                          /* !defined(HAVE_TEXT_START) && !defined(PDUMP) */

/*
 *      Return the address of the start of the data segment prior to
 *      doing an unexec.  After unexec the return value is undefined.
 *      See ecrt0.c for further information and definition of data_start.
 *
 *      Apparently, on BSD systems this is etext at startup.  On
 *      USG systems (swapping) this is highly mmu dependent and
 *      is also dependent on whether or not the program is running
 *      with shared text.  Generally there is a (possibly large)
 *      gap between end of text and start of data with shared text.
 *
 *      On Uniplus+ systems with shared text, data starts at a
 *      fixed address.  Each port (from a given oem) is generally
 *      different, and the specific value of the start of data can
 *      be obtained via the UniPlus+ specific "uvar" system call,
 *      however the method outlined in crt0.c seems to be more portable.
 *
 *      Probably what will have to happen when a USG unexec is available,
 *      at least on UniPlus, is temacs will have to be made unshared so
 *      that text and data are contiguous.  Then once loadup is complete,
 *      unexec will produce a shared executable where the data can be
 *      at the normal shared text boundary and the startofdata variable
 *      will be patched by unexec to the correct value.
 *
 */

#if defined(ORDINARY_LINK)
extern char **environ;
#endif

void *start_of_data(void)
{
#ifdef DATA_START
        return ((char *)DATA_START);
#else
#if defined (ORDINARY_LINK) || defined(PDUMP)
        /*
         * This is a hack.  Since we're not linking crt0.c or pre_crt0.c,
         * data_start isn't defined.  We take the address of environ, which
         * is known to live at or near the start of the system crt0.c, and
         * we don't sweat the handful of bytes that might lose.
         */
#if defined (HEAP_IN_DATA) && !defined(PDUMP)
        extern char *static_heap_base;
        if (!initialized)
                return static_heap_base;
#endif
        return ((char *)&environ);
#else
        extern int data_start;
        return ((char *)&data_start);
#endif                          /* ORDINARY_LINK */
#endif                          /* DATA_START */
}
#endif                          /* NEED_STARTS (not CANNOT_DUMP or not SYSTEM_MALLOC) */

#if !defined(CANNOT_DUMP) && !defined(PDUMP)
/* Some systems that cannot dump also cannot implement these.  */

/*
 *      Return the address of the end of the text segment prior to
 *      doing an unexec.  After unexec the return value is undefined.
 */

char *end_of_text(void)
{
#ifdef TEXT_END
        return ((char *)TEXT_END);
#else
        extern int etext;
        return ((char *)&etext);
#endif
}

/*
 *      Return the address of the end of the data segment prior to
 *      doing an unexec.  After unexec the return value is undefined.
 */

char *end_of_data(void)
{
#ifdef DATA_END
        return ((char *)DATA_END);
#else
        extern int edata;
        return ((char *)&edata);
#endif
}

#endif                          /* !defined(CANNOT_DUMP) && !defined(PDUMP) */
\f
/************************************************************************/
/*                          get the system name                         */
/************************************************************************/

/* init_system_name sets up the string for the Lisp function
   system-name to return. */

extern Lisp_Object Vsystem_name;

void init_system_name(void)
{
#if !defined (HAVE_GETHOSTNAME)
        struct utsname uts;
        uname(&uts);
        Vsystem_name = build_string(uts.nodename);
#else                           /* HAVE_GETHOSTNAME */
        unsigned int hostname_size = 256;
        char *hostname = (char *)alloca(hostname_size);

        /* Try to get the host name; if the buffer is too short, try
           again.  Apparently, the only indication gethostname gives of
           whether the buffer was large enough is the presence or absence
           of a '\0' in the string.  Eech.  */
        for (;;) {
                gethostname(hostname, hostname_size - 1);
                hostname[hostname_size - 1] = '\0';

                /* Was the buffer large enough for the '\0'?  */
                if (strlen(hostname) < (size_t) (hostname_size - 1))
                        break;

                hostname_size <<= 1;
                hostname = (char *)alloca(hostname_size);
        }
# if defined( HAVE_SOCKETS)
        /* Turn the hostname into the official, fully-qualified hostname.
           Don't do this if we're going to dump; this can confuse system
           libraries on some machines and make the dumped emacs core dump. */
#  ifndef CANNOT_DUMP
        if (initialized)
#  endif                        /* not CANNOT_DUMP */
                if (!strchr(hostname, '.')) {
#  if !(defined(HAVE_GETADDRINFO) && defined(HAVE_GETNAMEINFO))
                        struct hostent *hp = NULL;
                        int count;
#   ifdef TRY_AGAIN
                        for (count = 0; count < 10; count++) {
                                h_errno = 0;
#   endif
                                /* Some systems can't handle SIGALARM/SIGIO in gethostbyname(). */
                                stop_interrupts();
                                hp = gethostbyname(hostname);
                                start_interrupts();
#   ifdef TRY_AGAIN
                                if (!(hp == 0 && h_errno == TRY_AGAIN))
                                        break;
                                Fsleep_for(make_int(1));
                        }
#   endif
                        if (hp) {
                                const char *fqdn = (const char *)hp->h_name;
                                size_t len = 0;

                                if (!strchr(fqdn, '.')) {
                                        /* We still don't have a fully qualified domain name.
                                           Try to find one in the list of alternate names */
                                        char **alias = hp->h_aliases;
                                        while (*alias && !strchr(*alias, '.'))
                                                alias++;
                                        if (*alias)
                                                fqdn = *alias;
                                }
                                len = strlen(fqdn) + 1;
                                hostname = (char *)alloca(len);
                                xstrncpy(hostname, fqdn,len);
                        }
#  else                         /* !(HAVE_GETADDRINFO && HAVE_GETNAMEINFO) */
                        struct addrinfo hints, *res;

                        xzero(hints);
                        hints.ai_flags = AI_CANONNAME;
#ifdef IPV6_CANONICALIZE
                        hints.ai_family = AF_UNSPEC;
#else
                        hints.ai_family = PF_INET;
#endif
                        hints.ai_socktype = SOCK_STREAM;
                        hints.ai_protocol = 0;
                        if (!getaddrinfo(hostname, NULL, &hints, &res)) {
                                ssize_t canon_len=strlen(res->ai_canonname)+1;

                                hostname = (char *)alloca(canon_len);
                                xstrncpy(hostname, res->ai_canonname, canon_len);
                                freeaddrinfo(res);
                        }
#  endif                        /* !(HAVE_GETADDRINFO && HAVE_GETNAMEINFO) */
                }
# endif                         /* HAVE_SOCKETS */
        Vsystem_name = build_string(hostname);
#endif                          /* HAVE_GETHOSTNAME  */
        {
                Bufbyte *p;
                Bytecount i;

                for (i = 0, p = XSTRING_DATA(Vsystem_name);
                     i < XSTRING_LENGTH(Vsystem_name); i++, p++) {
                        if (*p == ' ' || *p == '\t')
                                *p = '-';
                }
        }
}
\f
/************************************************************************/
/*                        Emulation of select()                         */
/************************************************************************/

#ifndef HAVE_SELECT

ERROR:XEmacs requires a working select().
#endif                          /* not HAVE_SELECT */
\f/************************************************************************/
/*                      Emulation of signal stuff                       */
/************************************************************************/
/* BSD 4.1 crap deleted.  4.2 was released in 1983, for God's sake!  I
   can't imagine that anyone is actually running that OS any more.
   You can't use X under it (I think) because there's no select().
   Anyway, the signal stuff has all been changed.  If someone wants to
   get this stuff working again, look in the FSF Emacs sources. */
/* POSIX signals support - DJB */
#ifdef HAVE_SIGPROCMASK
/* #### Is there any reason this is static global rather than local? */
static struct sigaction new_action, old_action;

signal_handler_t sys_do_signal(int signal_number, signal_handler_t action)
{
#if 0

        /* XEmacs works better if system calls are *not* restarted.
           This allows C-g to interrupt reads and writes, on most systems.

           #### Another possibility is to just longjmp() out of the signal
           handler.  According to W.R. Stevens, this should be OK on all
           systems.  However, I don't want to deal with the potential
           evil ramifications of this at this point. */

#ifdef DGUX
        /* This gets us restartable system calls for efficiency.
           The "else" code will work as well. */
        return (berk_signal(signal_number, action));
#else
        sigemptyset(&new_action.sa_mask);
        new_action.sa_handler = action;
#if defined (SA_RESTART)
        /* Emacs mostly works better with restartable system services. If this
         * flag exists, we probably want to turn it on here.
         */
        new_action.sa_flags = SA_RESTART;
#else
        new_action.sa_flags = 0;
#endif
        sigaction(signal_number, &new_action, &old_action);
        return (old_action.sa_handler);
#endif                          /* DGUX */

#else                           /* not 0 */

        sigemptyset(&new_action.sa_mask);
        new_action.sa_handler = action;
#if defined (SA_INTERRUPT)      /* don't restart system calls, under SunOS */
        new_action.sa_flags = SA_INTERRUPT;
#else
        new_action.sa_flags = 0;
#endif
        sigaction(signal_number, &new_action, &old_action);
        return (signal_handler_t) (old_action.sa_handler);

#endif                          /* not 0 */
}

#elif defined (HAVE_SIGBLOCK)
/* We use sigvec() rather than signal() if we have it, because
   it lets us specify interruptible system calls. */
signal_handler_t sys_do_signal(int signal_number, signal_handler_t action)
{
        struct sigvec vec, ovec;

        vec.sv_handler = action;
        vec.sv_mask = 0;
#ifdef SV_INTERRUPT             /* don't restart system calls */
        vec.sv_flags = SV_INTERRUPT;
#else
        vec.sv_flags = 0;
#endif

        sigvec(signal_number, &vec, &ovec);

        return (ovec.sv_handler);
}

#endif                          /* HAVE_SIGBLOCK (HAVE_SIGPROCMASK) */
\f
/************************************************************************/
/*           Emulation of strerror() and errno support                  */
/************************************************************************/

#ifndef HAVE_STRERROR

#if !defined(NeXT) && !defined(__alpha) && !defined(MACH) && !defined(LINUX) && !defined(IRIX) && !defined(__NetBSD__)
/* Linux added here by Raymond L. Toy <toy@alydar.crd.ge.com> for XEmacs. */
/* Irix added here by gparker@sni-usa.com for XEmacs. */
/* NetBSD added here by James R Grinter <jrg@doc.ic.ac.uk> for XEmacs */
extern const char *sys_errlist[];
extern int sys_nerr;
#endif

#ifdef __NetBSD__
extern char *sys_errlist[];
extern int sys_nerr;
#endif

const char *strerror(int errnum)
{
        if (errnum >= 0 && errnum < sys_nerr)
                return sys_errlist[errnum];
        return ((const char *)GETTEXT("Unknown error"));
}

#endif                          /* ! HAVE_STRERROR */
\f
/************************************************************************/
/*                    Encapsulations of system calls                    */
/************************************************************************/

#define PATHNAME_CONVERT_OUT(path, pathout)             \
        TO_EXTERNAL_FORMAT(C_STRING, (path),            \
                           C_STRING_ALLOCA, (pathout),  \
                           Qfile_name);

/***************** low-level calls ****************/

/*
 *      On USG systems the system calls are INTERRUPTIBLE by signals
 *      that the user program has elected to catch.  Thus the system call
 *      must be retried in these cases.  To handle this without massive
 *      changes in the source code, we remap the standard system call names
 *      to names for our own functions in sysdep.c that do the system call
 *      with retries.  Actually, for portability reasons, it is good
 *      programming practice, as this example shows, to limit all actual
 *      system calls to a single occurrence in the source.  Sure, this
 *      adds an extra level of function call overhead but it is almost
 *      always negligible.   Fred Fish, Unisoft Systems Inc.
 */

/* Ben sez: read Dick Gabriel's essay about the Worse Is Better
   approach to programming and its connection to the silly
   interruptible-system-call business.  To find it, look on
   Jamie's home page (http://www.jwz.org/worse-is-better.html). */

#ifdef ENCAPSULATE_OPEN

int raw_open(const char *path, int oflag, ...)
{
        int mode;
        va_list ap;

        va_start(ap, oflag);
        mode = va_arg(ap, int);
        va_end(ap);
        return open(path, oflag, mode);
}

int sys_open(const char *path, int oflag, ...)
{
        int mode;
        va_list ap;
        char *pout;

        va_start(ap, oflag);
        mode = va_arg(ap, int);
        va_end(ap);

        PATHNAME_CONVERT_OUT(path, pout);

#ifdef INTERRUPTIBLE_OPEN
        {
                int rtnval;
                while ((rtnval = open(pout, oflag, mode)) == -1
                       && (errno == EINTR))
                        DO_NOTHING;
                return rtnval;
        }
#else
        return open(pout, oflag, mode);
#endif
}
#endif                          /* ENCAPSULATE_OPEN */

/* Like sys_open, only when open() is interrupted by EINTR, check for
   QUIT.  This allows the callers of this function to be interrupted
   with C-g when, say, reading from named pipes.  However, this should
   be used with caution, as it can GC.

   This function will not function as expected on systems where open()
   is not interrupted by C-g.  However, the worst that can happen is
   the fallback to simple open().  */
int interruptible_open(const char *path, int oflag, int mode)
{
        /* This function can GC */
        char *nrout;

        PATHNAME_CONVERT_OUT(path, nrout);

        for (;;) {
                int rtnval = open(nrout, oflag, mode);
                if (!(rtnval == -1 && errno == EINTR))
                        return rtnval;
                /* open() was interrupted.  Was QUIT responsible?  */
                QUIT;
        }
}

#ifdef ENCAPSULATE_CLOSE
int sys_close(int filedes)
{
#ifdef INTERRUPTIBLE_CLOSE
        int did_retry = 0;
        REGISTER int rtnval;

        while ((rtnval = close(filedes)) == -1 && (errno == EINTR))
                did_retry = 1;

        /* If close is interrupted SunOS 4.1 may or may not have closed the
           file descriptor.  If it did the second close will fail with
           errno = EBADF.  That means we have succeeded.  */
        if (rtnval == -1 && did_retry && errno == EBADF)
                return 0;

        return rtnval;
#else
        return close(filedes);
#endif
}
#endif                          /* ENCAPSULATE_CLOSE */

ssize_t sys_read_1(int fildes, void *buf, size_t nbyte, int allow_quit)
{
        ssize_t rtnval;

        /* No harm in looping regardless of the INTERRUPTIBLE_IO setting. */
        while ((rtnval = read(fildes, buf, nbyte)) == -1 && (errno == EINTR)) {
                if (allow_quit)
                        REALLY_QUIT;
        }
        return rtnval;
}

#ifdef ENCAPSULATE_READ
ssize_t sys_read(int fildes, void *buf, size_t nbyte)
{
        return sys_read_1(fildes, buf, nbyte, 0);
}
#endif                          /* ENCAPSULATE_READ */

ssize_t sys_write_1(int fildes, const void *buf, size_t nbyte, int allow_quit)
{
        ssize_t bytes_written = 0;
        const char *b = (const char *)buf;

        /* No harm in looping regardless of the INTERRUPTIBLE_IO setting. */
        while (nbyte > 0) {
                ssize_t rtnval = write(fildes, b, nbyte);

                if (allow_quit)
                        REALLY_QUIT;

                if (rtnval == -1) {
                        if (errno == EINTR)
                                continue;
                        else
                                return bytes_written ? bytes_written : -1;
                }
                b += rtnval;
                nbyte -= rtnval;
                bytes_written += rtnval;
        }
        return bytes_written;
}

#ifdef ENCAPSULATE_WRITE
ssize_t sys_write(int fildes, const void *buf, size_t nbyte)
{
        return sys_write_1(fildes, buf, nbyte, 0);
}
#endif                          /* ENCAPSULATE_WRITE */

/**************** stdio calls ****************/

/* There is at least some evidence that the stdio calls are interruptible
   just like the normal system calls, at least on some systems.  In any
   case, it doesn't hurt to encapsulate them. */

/* #### Should also encapsulate fflush().
   #### Should conceivably encapsulate getchar() etc.  What a pain! */

#ifdef ENCAPSULATE_FOPEN
FILE *sys_fopen(const char *path, const char *type)
{
        char *pout;

        PATHNAME_CONVERT_OUT(path, pout);
#if defined (INTERRUPTIBLE_OPEN)
        {
                FILE *rtnval;
                while (!(rtnval = fopen(pout, type)) && (errno == EINTR))
                        DO_NOTHING;
                return rtnval;
        }
#else
        return fopen(pout, type);
#endif
}
#endif                          /* ENCAPSULATE_FOPEN */

#ifdef ENCAPSULATE_FCLOSE
int sys_fclose(FILE * stream)
{
#ifdef INTERRUPTIBLE_CLOSE
        int fd     = fileno(stream);
        int rtnval = fclose(stream);

        if (rtnval == EOF && (errno == EINTR))
                while (((rtnval=close(fd))<0) && (errno == EINTR));
        return rtnval;
#else
        return fclose(stream);
#endif
}
#endif                          /* ENCAPSULATE_FCLOSE */

#ifdef ENCAPSULATE_FREAD
size_t sys_fread(void *ptr, size_t size, size_t nitem, FILE * stream)
{
#ifdef INTERRUPTIBLE_IO
        size_t rtnval;
        size_t items_read = 0;
        char *b = (char *)ptr;

        while (nitem > 0) {
                rtnval = fread(b, size, nitem, stream);
                if (rtnval == 0) {
                        if (ferror(stream) && errno == EINTR)
                                continue;
                        else
                                return items_read;
                }
                b += size * rtnval;
                nitem -= rtnval;
                items_read += rtnval;
        }
        return (items_read);
#else
        return fread(ptr, size, nitem, stream);
#endif
}
#endif                          /* ENCAPSULATE_FREAD */

#ifdef ENCAPSULATE_FWRITE
size_t sys_fwrite(const void *ptr, size_t size, size_t nitem, FILE * stream)
{
#ifdef INTERRUPTIBLE_IO
        size_t rtnval;
        size_t items_written = 0;
        const char *b = (const char *)ptr;

        while (nitem > 0) {
                rtnval = fwrite(b, size, nitem, stream);
                if (rtnval == 0) {
                        if (ferror(stream) && errno == EINTR)
                                continue;
                        else
                                return items_written;
                }
                b += size * rtnval;
                nitem -= rtnval;
                items_written += rtnval;
        }
        return (items_written);
#else
        return fwrite(ptr, size, nitem, stream);
#endif
}
#endif                          /* ENCAPSULATE_FWRITE */

/********************* directory calls *******************/

#ifdef ENCAPSULATE_CHDIR
int sys_chdir(const char *path)
{
        char *pout;
        PATHNAME_CONVERT_OUT(path, pout);
        return chdir(pout);
}
#endif                          /* ENCAPSULATE_CHDIR */

#ifdef ENCAPSULATE_MKDIR
int sys_mkdir(const char *path, mode_t mode)
{
        char *pout;
        PATHNAME_CONVERT_OUT(path, pout);
        return mkdir(pout, mode);
}
#endif                          /* ENCAPSULATE_MKDIR */

#ifdef ENCAPSULATE_OPENDIR
DIR *sys_opendir(const char *filename)
{
        DIR *rtnval;
        char *fout;
        PATHNAME_CONVERT_OUT(filename, fout);

        while (!(rtnval = opendir(fout))
               && (errno == EINTR)) ;
        return rtnval;
}
#endif                          /* ENCAPSULATE_OPENDIR */

#ifdef ENCAPSULATE_READDIR
DIRENTRY *sys_readdir(DIR * dirp)
{
        DIRENTRY *rtnval;

        /* Apparently setting errno is necessary on some systems?
           Maybe readdir() doesn't always set errno ?! */
        while (!(errno = 0, rtnval = readdir(dirp))
               && (errno == EINTR)) ;
#ifndef MULE
        return rtnval;
#else                           /* MULE */
        if (rtnval == NULL)     /* End of directory */
                return NULL;
        {
                const Extbyte *const external_name =
                    (const Extbyte *)rtnval->d_name;
                Extcount external_len = strlen(rtnval->d_name);
                const Bufbyte *internal_name;
                Bytecount internal_len;

                TO_INTERNAL_FORMAT(DATA, (external_name, external_len),
                                   ALLOCA, (internal_name, internal_len),
                                   Qfile_name);

                /* check for common case of ASCII filename */
                if (internal_len == external_len &&
                    !memcmp(external_name, internal_name, internal_len))
                        return rtnval;

                {               /* Non-ASCII filename */
                        static Bufbyte_dynarr *internal_DIRENTRY;
                        if (!internal_DIRENTRY)
                                internal_DIRENTRY = Dynarr_new(Bufbyte);
                        else
                                Dynarr_reset(internal_DIRENTRY);

                        Dynarr_add_many(internal_DIRENTRY, (Bufbyte *) rtnval,
                                        offsetof(DIRENTRY, d_name));

                        Dynarr_add_many(internal_DIRENTRY, internal_name,
                                        internal_len);
                        Dynarr_add(internal_DIRENTRY, '\0');    /* NUL-terminate */
                        return (DIRENTRY *) Dynarr_atp(internal_DIRENTRY, 0);
                }
        }
#endif                          /* MULE */
}
#endif                          /* ENCAPSULATE_READDIR */

#ifdef ENCAPSULATE_CLOSEDIR
int sys_closedir(DIR * dirp)
{
        int rtnval;

        while ((rtnval = closedir(dirp)) == -1 && (errno == EINTR)) ;
        return rtnval;
}
#endif                          /* ENCAPSULATE_CLOSEDIR */

#ifdef ENCAPSULATE_RMDIR
int sys_rmdir(const char *path)
{
        char *pout;
        PATHNAME_CONVERT_OUT(path, pout);
        return rmdir(pout);
}
#endif                          /* ENCAPSULATE_RMDIR */

/***************** file-information calls ******************/

#ifdef ENCAPSULATE_ACCESS
int sys_access(const char *path, int mode)
{
        char *pout;
        PATHNAME_CONVERT_OUT(path, pout);
        return access(pout, mode);
}
#endif                          /* ENCAPSULATE_ACCESS */

#ifdef HAVE_EACCESS
#ifdef ENCAPSULATE_EACCESS
int sys_eaccess(const char *path, int mode)
{
        char *pout;
        PATHNAME_CONVERT_OUT(path, pout);
        return eaccess(pout, mode);
}
#endif                          /* ENCAPSULATE_EACCESS */
#endif                          /* HAVE_EACCESS */

#ifdef ENCAPSULATE_LSTAT
int sys_lstat(const char *path, struct stat *buf)
{
        char *pout;
        PATHNAME_CONVERT_OUT(path, pout);
        return lstat(pout, buf);
}
#endif                          /* ENCAPSULATE_LSTAT */

#ifdef ENCAPSULATE_READLINK
int sys_readlink(const char *path, char *buf, size_t bufsiz)
{
        char *pout;
        PATHNAME_CONVERT_OUT(path, pout);
        /* #### currently we don't do conversions on the incoming data */
        return readlink(pout, buf, bufsiz);
}
#endif                          /* ENCAPSULATE_READLINK */

#ifdef ENCAPSULATE_FSTAT
int sys_fstat(int fd, struct stat *buf)
{
        return fstat(fd, buf);
}
#endif                          /* ENCAPSULATE_FSTAT */

int sxemacs_stat(const char *path, struct stat *buf)
{
        char *pout;
        PATHNAME_CONVERT_OUT(path, pout);
        return stat(pout, buf);
}

/****************** file-manipulation calls *****************/

#ifdef ENCAPSULATE_CHMOD
int sys_chmod(const char *path, mode_t mode)
{
        char *pout;
        PATHNAME_CONVERT_OUT(path, pout);
        return chmod(pout, mode);
}
#endif                          /* ENCAPSULATE_CHMOD */

#ifdef ENCAPSULATE_CREAT
int sys_creat(const char *path, mode_t mode)
{
        char *pout;
        PATHNAME_CONVERT_OUT(path, pout);
        return creat(pout, mode);
}
#endif                          /* ENCAPSULATE_CREAT */

#ifdef ENCAPSULATE_LINK
int sys_link(const char *existing, const char *new)
{
        char *eout, *nout;
        PATHNAME_CONVERT_OUT(existing, eout);
        PATHNAME_CONVERT_OUT(new, nout);
        return link(eout, nout);
}
#endif                          /* ENCAPSULATE_LINK */

#ifdef ENCAPSULATE_RENAME
int sys_rename(const char *old, const char *new)
{
        char *oout, *nout;
        PATHNAME_CONVERT_OUT(old, oout);
        PATHNAME_CONVERT_OUT(new, nout);
        return rename(oout, nout);
}
#endif                          /* ENCAPSULATE_RENAME */

#ifdef ENCAPSULATE_SYMLINK
int sys_symlink(const char *name1, const char *name2)
{
        char *n1out, *n2out;
        PATHNAME_CONVERT_OUT(name1, n1out);
        PATHNAME_CONVERT_OUT(name2, n2out);
        return symlink(n1out, n2out);
}
#endif                          /* ENCAPSULATE_SYMLINK */

#ifdef ENCAPSULATE_UNLINK
int sys_unlink(const char *path)
{
        char *pout;
        PATHNAME_CONVERT_OUT(path, pout);
        return unlink(pout);
}
#endif                          /* ENCAPSULATE_UNLINK */

#ifdef ENCAPSULATE_EXECVP
int sys_execvp(const char *path, char *const *argv)
{
        int i, argc;
        char *pout;

        PATHNAME_CONVERT_OUT(path, pout);
        for (argc = 0; argv[argc]; argc++);
        {
                /* c99ified */
                char *new_argv[argc+1];
                for (i = 0; i < argc; i++) {
                        PATHNAME_CONVERT_OUT(argv[i], new_argv[i]);
                }
                new_argv[argc] = NULL;
                return execvp(pout, new_argv);
        }
}
#endif                          /* ENCAPSULATE_EXECVP */
\f
/************************************************************************/
/*                  Emulations of missing system calls                  */
/************************************************************************/

/***** (these are primarily required for USG, it seems) *****/

#ifndef HAVE_GETCWD
char *getcwd(char *pathname, size_t size)
{
        return getwd(pathname);
}
#endif                          /* emulate getcwd */


/*
 *      Emulate rename using unlink/link.  Note that this is
 *      only partially correct.  Also, doesn't enforce restriction
 *      that files be of same type (regular->regular, dir->dir, etc).
 */

#ifndef HAVE_RENAME
int rename(const char *from, const char *to)
{
        if (access(from, 0) == 0) {
                unlink(to);
                if (link(from, to) == 0)
                        if (unlink(from) == 0)
                                return (0);
        }
        return (-1);
}
#endif                          /* HAVE_RENAME */

#ifdef HPUX
#ifndef HAVE_PERROR

/* HPUX curses library references perror, but as far as we know
   it won't be called.  Anyway this definition will do for now.  */

perror(void)
{
}

#endif                          /* not HAVE_PERROR */
#endif                          /* HPUX */

#ifndef HAVE_DUP2

/*
 *      Emulate BSD dup2.  First close newd if it already exists.
 *      Then, attempt to dup oldd.  If not successful, call dup2 recursively
 *      until we are, then close the unsuccessful ones.
 */

int dup2(int oldd, int newd)
{
        int fd, ret;

        sys_close(newd);

#ifdef F_DUPFD
        fd = fcntl(oldd, F_DUPFD, newd);
        if (fd != newd)
                error("can't dup2 (%i,%i) : %s", oldd, newd, strerror(errno));
#else
        fd = dup(old);
        if (fd == -1)
                return -1;
        if (fd == new)
                return new;
        ret = dup2(old, new);
        sys_close(fd);
        return ret;
#endif                          /*  F_DUPFD */
}

#endif                          /* not HAVE_DUP2 */

/*
 *      Gettimeofday.  Simulate as much as possible.  Only accurate
 *      to nearest second.  Emacs doesn't use tzp so ignore it for now.
 */

#if !defined (HAVE_GETTIMEOFDAY)

int gettimeofday(struct timeval *tp, struct timezone *tzp)
{
        extern long time();

        tp->tv_sec = time((long *)0);
        tp->tv_usec = 0;
        if (tzp != 0)
                tzp->tz_minuteswest = -1;
        return (0);
}

#endif                          /* !HAVE_GETTIMEOFDAY */

/* No need to encapsulate utime and utimes explicitly because all
   access to those functions goes through the following. */

int set_file_times(Lisp_Object path, EMACS_TIME atime, EMACS_TIME mtime)
{
#if defined (HAVE_UTIME)
        struct utimbuf utb;
        Extbyte *filename;
        utb.actime = EMACS_SECS(atime);
        utb.modtime = EMACS_SECS(mtime);
        LISP_STRING_TO_EXTERNAL(path, filename, Qfile_name);
        return utime(filename, &utb);
#elif defined (HAVE_UTIMES)
        struct timeval tv[2];
        Extbyte *filename;
        tv[0] = atime;
        tv[1] = mtime;
        LISP_STRING_TO_EXTERNAL(path, filename, Qfile_name);
        return utimes(filename, tv);
#else
        /* No file times setting function available. */
        return -1;
#endif
}

/* */

static long ticks_per_second;
static long orig_user_ticks, orig_system_ticks;
EMACS_TIME orig_real_time;

static int process_times_available;

/* Return the relative user and system tick count.  We try to
   maintain calculations in terms of integers as long as possible
   for increased accuracy. */

static int get_process_times_1(long *user_ticks, long *system_ticks)
{
#if defined (_SC_CLK_TCK) || defined (CLK_TCK)
        /* We have the POSIX times() function available. */
        struct tms tttt;
        times(&tttt);
        *user_ticks = (long)tttt.tms_utime;
        *system_ticks = (long)tttt.tms_stime;
        return 1;
#elif defined (CLOCKS_PER_SEC)
        *user_ticks = (long)clock();
        *system_ticks = 0;
        return 1;
#else
        return 0;
#endif
}

void init_process_times_very_early(void)
{
#if defined (_SC_CLK_TCK)
        ticks_per_second = sysconf(_SC_CLK_TCK);
#elif defined (CLK_TCK)
        ticks_per_second = CLK_TCK;
#elif defined (CLOCKS_PER_SEC)
        ticks_per_second = CLOCKS_PER_SEC;
#endif

        process_times_available = get_process_times_1(&orig_user_ticks,
                                                      &orig_system_ticks);
        EMACS_GET_TIME(orig_real_time);
}

/* Return the user and system times used up by this process so far. */
void
get_process_times(double *user_time, double *system_time, double *real_time)
{
        EMACS_TIME curr_real_time;
        EMACS_TIME elapsed_time;
        long curr_user_ticks, curr_system_ticks;

        EMACS_GET_TIME(curr_real_time);
        EMACS_SUB_TIME(elapsed_time, curr_real_time, orig_real_time);
        *real_time = (EMACS_SECS(elapsed_time)
                      + ((double)EMACS_USECS(elapsed_time)) / 1000000);
        if (get_process_times_1(&curr_user_ticks, &curr_system_ticks)) {
                *user_time = (((double)(curr_user_ticks - orig_user_ticks))
                              / ticks_per_second);
                *system_time =
                    (((double)(curr_system_ticks - orig_system_ticks))
                     / ticks_per_second);
        } else {
                /* A lame OS */
                *user_time = *real_time;
                *system_time = 0;
        }
}

#ifndef HAVE_RANDOM
#ifdef random
#define HAVE_RANDOM
#endif
#endif

/* Figure out how many bits the system's random number generator uses.
   `random' and `lrand48' are assumed to return 31 usable bits.
   BSD `rand' returns a 31 bit value but the low order bits are unusable;
   so we'll shift it and treat it like the 15-bit USG `rand'.  */

#ifndef RAND_BITS
# ifdef HAVE_RANDOM
#  define RAND_BITS 31
# else                          /* !HAVE_RANDOM */
#  ifdef HAVE_LRAND48
#   define RAND_BITS 31
#   define random lrand48
#  else                         /* !HAVE_LRAND48 */
#   define RAND_BITS 15
#   if RAND_MAX == 32767
#    define random rand
#   else                        /* RAND_MAX != 32767 */
#    if RAND_MAX == 2147483647
#     define random() (rand () >> 16)
#    else                       /* RAND_MAX != 2147483647 */
#     ifdef USG
#      define random rand
#     else
#      define random() (rand () >> 16)
#     endif                     /* !BSD */
#    endif                      /* RAND_MAX != 2147483647 */
#   endif                       /* RAND_MAX != 32767 */
#  endif                        /* !HAVE_LRAND48 */
# endif                         /* !HAVE_RANDOM */
#endif                          /* !RAND_BITS */

void seed_random(long arg);
void seed_random(long arg)
{
#ifdef HAVE_RANDOM
        srandom((unsigned int)arg);
#else
# ifdef HAVE_LRAND48
        srand48(arg);
# else
        srand((unsigned int)arg);
# endif
#endif
#if defined HAVE_MPZ && (defined WITH_GMP || defined WITH_MP)
        bigz_random_seed((unsigned long)arg);
#endif
}

/*
 * Build a full Emacs-sized word out of whatever we've got.
 * This suffices even for a 64-bit architecture with a 15-bit rand.
 */
long get_random(void);
long get_random(void)
{
        long val = random();
#if INT_VALBITS > RAND_BITS
        val = (val << RAND_BITS) ^ random();
#if INT_VALBITS > 2*RAND_BITS
        val = (val << RAND_BITS) ^ random();
#if INT_VALBITS > 3*RAND_BITS
        val = (val << RAND_BITS) ^ random();
#if INT_VALBITS > 4*RAND_BITS
        val = (val << RAND_BITS) ^ random();
#endif                          /* need at least 5 */
#endif                          /* need at least 4 */
#endif                          /* need at least 3 */
#endif                          /* need at least 2 */
        return val & (EMACS_INT) ((1UL << INT_VALBITS) - 1);
}
\f
/************************************************************************/
/*               Strings corresponding to defined signals               */
/************************************************************************/

#if !defined (SYS_SIGLIST_DECLARED) && !defined (HAVE_SYS_SIGLIST) && !defined(HAVE_DECL_SYS_SIGLIST)

#ifdef USG
#ifdef AIX
#define SXE_SYS_SIGLIST_DECLARED 1
const char *sys_siglist[NSIG + 1] = {
        /* AIX has changed the signals a bit */
        DEFER_GETTEXT("bogus signal"),  /* 0 */
        DEFER_GETTEXT("hangup"),        /* 1  SIGHUP */
        DEFER_GETTEXT("interrupt"),     /* 2  SIGINT */
        DEFER_GETTEXT("quit"),  /* 3  SIGQUIT */
        DEFER_GETTEXT("illegal instruction"),   /* 4  SIGILL */
        DEFER_GETTEXT("trace trap"),    /* 5  SIGTRAP */
        DEFER_GETTEXT("IOT instruction"),       /* 6  SIGIOT */
        DEFER_GETTEXT("crash likely"),  /* 7  SIGDANGER */
        DEFER_GETTEXT("floating point exception"),      /* 8  SIGFPE */
        DEFER_GETTEXT("kill"),  /* 9  SIGKILL */
        DEFER_GETTEXT("bus error"),     /* 10 SIGBUS */
        DEFER_GETTEXT("segmentation violation"),        /* 11 SIGSEGV */
        DEFER_GETTEXT("bad argument to system call"),   /* 12 SIGSYS */
        DEFER_GETTEXT("write on a pipe with no one to read it"),        /* 13 SIGPIPE */
        DEFER_GETTEXT("alarm clock"),   /* 14 SIGALRM */
        DEFER_GETTEXT("software termination signal"),   /* 15 SIGTERM */
        DEFER_GETTEXT("user defined signal 1"), /* 16 SIGUSR1 */
        DEFER_GETTEXT("user defined signal 2"), /* 17 SIGUSR2 */
        DEFER_GETTEXT("death of a child"),      /* 18 SIGCLD */
        DEFER_GETTEXT("power-fail restart"),    /* 19 SIGPWR */
        DEFER_GETTEXT("bogus signal"),  /* 20 */
        DEFER_GETTEXT("bogus signal"),  /* 21 */
        DEFER_GETTEXT("bogus signal"),  /* 22 */
        DEFER_GETTEXT("bogus signal"),  /* 23 */
        DEFER_GETTEXT("bogus signal"),  /* 24 */
        DEFER_GETTEXT("LAN I/O interrupt"),     /* 25 SIGAIO */
        DEFER_GETTEXT("PTY I/O interrupt"),     /* 26 SIGPTY */
        DEFER_GETTEXT("I/O intervention required"),     /* 27 SIGIOINT */
#ifdef AIXHFT
        DEFER_GETTEXT("HFT grant"),     /* 28 SIGGRANT */
        DEFER_GETTEXT("HFT retract"),   /* 29 SIGRETRACT */
        DEFER_GETTEXT("HFT sound done"),        /* 30 SIGSOUND */
        DEFER_GETTEXT("HFT input ready"),       /* 31 SIGMSG */
#endif
        0
};
#else                           /* USG, not AIX */
#define SXE_SYS_SIGLIST_DECLARED 1
const char *sys_siglist[NSIG + 1] = {
        DEFER_GETTEXT("bogus signal"),  /* 0 */
        DEFER_GETTEXT("hangup"),        /* 1  SIGHUP */
        DEFER_GETTEXT("interrupt"),     /* 2  SIGINT */
        DEFER_GETTEXT("quit"),  /* 3  SIGQUIT */
        DEFER_GETTEXT("illegal instruction"),   /* 4  SIGILL */
        DEFER_GETTEXT("trace trap"),    /* 5  SIGTRAP */
        DEFER_GETTEXT("IOT instruction"),       /* 6  SIGIOT */
        DEFER_GETTEXT("EMT instruction"),       /* 7  SIGEMT */
        DEFER_GETTEXT("floating point exception"),      /* 8  SIGFPE */
        DEFER_GETTEXT("kill"),  /* 9  SIGKILL */
        DEFER_GETTEXT("bus error"),     /* 10 SIGBUS */
        DEFER_GETTEXT("segmentation violation"),        /* 11 SIGSEGV */
        DEFER_GETTEXT("bad argument to system call"),   /* 12 SIGSYS */
        DEFER_GETTEXT("write on a pipe with no one to read it"),        /* 13 SIGPIPE */
        DEFER_GETTEXT("alarm clock"),   /* 14 SIGALRM */
        DEFER_GETTEXT("software termination signal"),   /* 15 SIGTERM */
        DEFER_GETTEXT("user defined signal 1"), /* 16 SIGUSR1 */
        DEFER_GETTEXT("user defined signal 2"), /* 17 SIGUSR2 */
        DEFER_GETTEXT("death of a child"),      /* 18 SIGCLD */
        DEFER_GETTEXT("power-fail restart"),    /* 19 SIGPWR */
#ifdef sun
        DEFER_GETTEXT("window size changed"),   /* 20 SIGWINCH */
        DEFER_GETTEXT("urgent socket condition"),       /* 21 SIGURG */
        DEFER_GETTEXT("pollable event occurred"),       /* 22 SIGPOLL */
        DEFER_GETTEXT("stop (cannot be caught or ignored)"),    /*  23 SIGSTOP */
        DEFER_GETTEXT("user stop requested from tty"),  /* 24 SIGTSTP */
        DEFER_GETTEXT("stopped process has been continued"),    /* 25 SIGCONT */
        DEFER_GETTEXT("background tty read attempted"), /* 26 SIGTTIN */
        DEFER_GETTEXT("background tty write attempted"),        /* 27 SIGTTOU */
        DEFER_GETTEXT("virtual timer expired"), /* 28 SIGVTALRM */
        DEFER_GETTEXT("profiling timer expired"),       /* 29 SIGPROF */
        DEFER_GETTEXT("exceeded cpu limit"),    /* 30 SIGXCPU */
        DEFER_GETTEXT("exceeded file size limit"),      /* 31 SIGXFSZ */
        DEFER_GETTEXT("process's lwps are blocked"),    /* 32 SIGWAITING */
        DEFER_GETTEXT("special signal used by thread library"), /* 33 SIGLWP */
#ifdef SIGFREEZE
        DEFER_GETTEXT("special signal used by CPR"),    /* 34 SIGFREEZE */
#endif
#ifdef SIGTHAW
        DEFER_GETTEXT("special signal used by CPR"),    /* 35 SIGTHAW */
#endif
#endif                          /* sun */
        0
};
#endif                          /* not AIX */
#endif                          /* USG */
#ifdef DGUX
#define SXE_SYS_SIGLIST_DECLARED 1
const char *sys_siglist[NSIG + 1] = {
        DEFER_GETTEXT("null signal"),   /*  0 SIGNULL   */
        DEFER_GETTEXT("hangup"),        /*  1 SIGHUP    */
        DEFER_GETTEXT("interrupt"),     /*  2 SIGINT    */
        DEFER_GETTEXT("quit"),  /*  3 SIGQUIT   */
        DEFER_GETTEXT("illegal instruction"),   /*  4 SIGILL    */
        DEFER_GETTEXT("trace trap"),    /*  5 SIGTRAP   */
        DEFER_GETTEXT("abort termination"),     /*  6 SIGABRT   */
        DEFER_GETTEXT("SIGEMT"),        /*  7 SIGEMT    */
        DEFER_GETTEXT("floating point exception"),      /*  8 SIGFPE    */
        DEFER_GETTEXT("kill"),  /*  9 SIGKILL   */
        DEFER_GETTEXT("bus error"),     /* 10 SIGBUS    */
        DEFER_GETTEXT("segmentation violation"),        /* 11 SIGSEGV   */
        DEFER_GETTEXT("bad argument to system call"),   /* 12 SIGSYS    */
        DEFER_GETTEXT("write on a pipe with no reader"),        /* 13 SIGPIPE   */
        DEFER_GETTEXT("alarm clock"),   /* 14 SIGALRM   */
        DEFER_GETTEXT("software termination signal"),   /* 15 SIGTERM   */
        DEFER_GETTEXT("user defined signal 1"), /* 16 SIGUSR1   */
        DEFER_GETTEXT("user defined signal 2"), /* 17 SIGUSR2   */
        DEFER_GETTEXT("child stopped or terminated"),   /* 18 SIGCLD    */
        DEFER_GETTEXT("power-fail restart"),    /* 19 SIGPWR    */
        DEFER_GETTEXT("window size changed"),   /* 20 SIGWINCH  */
        DEFER_GETTEXT("undefined"),     /* 21           */
        DEFER_GETTEXT("pollable event occurred"),       /* 22 SIGPOLL   */
        DEFER_GETTEXT("sendable stop signal not from tty"),     /* 23 SIGSTOP   */
        DEFER_GETTEXT("stop signal from tty"),  /* 24 SIGSTP    */
        DEFER_GETTEXT("continue a stopped process"),    /* 25 SIGCONT   */
        DEFER_GETTEXT("attempted background tty read"), /* 26 SIGTTIN   */
        DEFER_GETTEXT("attempted background tty write"),        /* 27 SIGTTOU   */
        DEFER_GETTEXT("undefined"),     /* 28           */
        DEFER_GETTEXT("undefined"),     /* 29           */
        DEFER_GETTEXT("undefined"),     /* 30           */
        DEFER_GETTEXT("undefined"),     /* 31           */
        DEFER_GETTEXT("undefined"),     /* 32           */
        DEFER_GETTEXT("socket (TCP/IP) urgent data arrival"),   /* 33 SIGURG    */
        DEFER_GETTEXT("I/O is possible"),       /* 34 SIGIO     */
        DEFER_GETTEXT("exceeded cpu time limit"),       /* 35 SIGXCPU   */
        DEFER_GETTEXT("exceeded file size limit"),      /* 36 SIGXFSZ   */
        DEFER_GETTEXT("virtual time alarm"),    /* 37 SIGVTALRM */
        DEFER_GETTEXT("profiling time alarm"),  /* 38 SIGPROF   */
        DEFER_GETTEXT("undefined"),     /* 39           */
        DEFER_GETTEXT("file record locks revoked"),     /* 40 SIGLOST   */
        DEFER_GETTEXT("undefined"),     /* 41           */
        DEFER_GETTEXT("undefined"),     /* 42           */
        DEFER_GETTEXT("undefined"),     /* 43           */
        DEFER_GETTEXT("undefined"),     /* 44           */
        DEFER_GETTEXT("undefined"),     /* 45           */
        DEFER_GETTEXT("undefined"),     /* 46           */
        DEFER_GETTEXT("undefined"),     /* 47           */
        DEFER_GETTEXT("undefined"),     /* 48           */
        DEFER_GETTEXT("undefined"),     /* 49           */
        DEFER_GETTEXT("undefined"),     /* 50           */
        DEFER_GETTEXT("undefined"),     /* 51           */
        DEFER_GETTEXT("undefined"),     /* 52           */
        DEFER_GETTEXT("undefined"),     /* 53           */
        DEFER_GETTEXT("undefined"),     /* 54           */
        DEFER_GETTEXT("undefined"),     /* 55           */
        DEFER_GETTEXT("undefined"),     /* 56           */
        DEFER_GETTEXT("undefined"),     /* 57           */
        DEFER_GETTEXT("undefined"),     /* 58           */
        DEFER_GETTEXT("undefined"),     /* 59           */
        DEFER_GETTEXT("undefined"),     /* 60           */
        DEFER_GETTEXT("undefined"),     /* 61           */
        DEFER_GETTEXT("undefined"),     /* 62           */
        DEFER_GETTEXT("undefined"),     /* 63           */
        DEFER_GETTEXT("notification message in mess. queue"),   /* 64 SIGDGNOTIFY */
        0
};
#endif                          /* DGUX */

#endif                          /* ! SYS_SIGLIST_DECLARED && ! HAVE_SYS_SIGLIST */
\f
/************************************************************************/
/*         Directory routines for systems that don't have them          */
/************************************************************************/

#ifdef SYSV_SYSTEM_DIR

#include <dirent.h>

#if defined(BROKEN_CLOSEDIR) || !defined(HAVE_CLOSEDIR)
int closedir(DIR * dirp)
{                               /* stream from opendir */
        int rtnval;

        rtnval = sys_close(dirp->dd_fd);

        /* Some systems (like Solaris) allocate the buffer and the DIR all
           in one block.  Why in the world are we freeing this ourselves
           anyway?  */
#if ! (defined (sun) && defined (USG5_4))
        xfree((char *)dirp->dd_buf);    /* directory block defined in <dirent.h> */
#endif
        xfree((char *)dirp);
        return (rtnval);
}
#endif                          /* BROKEN_CLOSEDIR or not HAVE_CLOSEDIR */
#endif                          /* SYSV_SYSTEM_DIR */

#ifdef NONSYSTEM_DIR_LIBRARY

DIR *opendir(const char *filename)
{                               /* name of directory */
        DIR *dirp;              /* -> malloc'ed storage */
        int fd;                 /* file descriptor for read */
        struct stat sbuf;       /* result of fstat */

        fd = sys_open(filename, O_RDONLY);
        if (fd < 0)
                return 0;

        if (fstat(fd, &sbuf) < 0
            || (sbuf.st_mode & S_IFMT) != S_IFDIR
            || (dirp = xnew(DIR)) == 0) {
                sys_close(fd);
                return 0;       /* bad luck today */
        }

        dirp->dd_fd = fd;
        dirp->dd_loc = dirp->dd_size = 0;       /* refill needed */

        return dirp;
}

void closedir(DIR * dirp)
{                               /* stream from opendir */
        sys_close(dirp->dd_fd);
        xfree(dirp);
}

#define DIRSIZ  14
struct olddir {
        ino_t od_ino;           /* inode */
        char od_name[DIRSIZ];   /* filename */
};

static struct direct dir_static;        /* simulated directory contents */

/* ARGUSED */
struct direct *readdir(DIR * dirp)
{                               /* stream from opendir */
        struct olddir *dp;      /* -> directory data */

        for (;;) {
                if (dirp->dd_loc >= dirp->dd_size)
                        dirp->dd_loc = dirp->dd_size = 0;

                if (dirp->dd_size == 0  /* refill buffer */
                    && (dirp->dd_size =
                        sys_read(dirp->dd_fd, dirp->dd_buf, DIRBLKSIZ)) <= 0)
                        return 0;

                dp = (struct olddir *)&dirp->dd_buf[dirp->dd_loc];
                dirp->dd_loc += sizeof(struct olddir);

                if (dp->od_ino != 0) {  /* not deleted entry */
                        dir_static.d_ino = dp->od_ino;
                        xstrncpy(dir_static.d_name, dp->od_name, DIRSIZ);
                        dir_static.d_name[DIRSIZ] = '\0';
                        dir_static.d_namlen = strlen(dir_static.d_name);
                        dir_static.d_reclen = sizeof(struct direct)
                            - MAXNAMLEN + 3
                            + dir_static.d_namlen - dir_static.d_namlen % 4;
                        return &dir_static;     /* -> simulated structure */
                }
        }
}

#endif                          /* NONSYSTEM_DIR_LIBRARY */
\f
/* mkdir and rmdir functions, for systems which don't have them.  */

#ifndef HAVE_MKDIR
/*
 * Written by Robert Rother, Mariah Corporation, August 1985.
 *
 * If you want it, it's yours.  All I ask in return is that if you
 * figure out how to do this in a Bourne Shell script you send me
 * a copy.
 *                                      sdcsvax!rmr or rmr@uscd
 *
 * Severely hacked over by John Gilmore to make a 4.2BSD compatible
 * subroutine.  11Mar86; hoptoad!gnu
 *
 * Modified by rmtodd@uokmax 6-28-87 -- when making an already existing dir,
 * subroutine didn't return EEXIST.  It does now.
 */

/*
 * Make a directory.
 */
#ifdef MKDIR_PROTOTYPE
MKDIR_PROTOTYPE
#else
int mkdir(const char *dpath, int dmode)
#endif
{
        int cpid, status, fd;
        struct stat statbuf;

        if (stat(dpath, &statbuf) == 0) {       /* we do want stat() here */
                errno = EEXIST; /* Stat worked, so it already exists */
                return -1;
        }

        /* If stat fails for a reason other than non-existence, return error */
        if (errno != ENOENT)
                return -1;

        synch_process_alive = 1;
        switch (cpid = fork()) {

        case -1:                /* Error in fork() */
                return -1;      /* Errno is set already */

        case 0:         /* Child process */
                {
                        /*
                         * Cheap hack to set mode of new directory.  Since this
                         * child process is going away anyway, we zap its umask.
                         * ####, this won't suffice to set SUID, SGID, etc. on this
                         * directory.  Does anybody care?
                         */
                        status = umask(0);      /* Get current umask */
                        status = umask(status | (0777 & ~dmode));       /* Set for mkdir */
                        fd = sys_open("/dev/null", O_RDWR);
                        if (fd >= 0) {
                                if (fd != STDIN_FILENO)
                                        dup2(fd, STDIN_FILENO);
                                if (fd != STDOUT_FILENO)
                                        dup2(fd, STDOUT_FILENO);
                                if (fd != STDERR_FILENO)
                                        dup2(fd, STDERR_FILENO);
                        }
                        execl("/bin/mkdir", "mkdir", dpath, (char *)0);
                        _exit(-1);      /* Can't exec /bin/mkdir */
                }

        default:                /* Parent process */
                wait_for_termination(cpid);
        }

        if (synch_process_death != 0 || synch_process_retcode != 0) {
                errno = EIO;    /* We don't know why, but */
                return -1;      /* /bin/mkdir failed */
        }

        return 0;
}
#endif                          /* not HAVE_MKDIR */

#ifndef HAVE_RMDIR
int rmdir(const char *dpath)
{
        int cpid, status, fd;
        struct stat statbuf;

        if (stat(dpath, &statbuf) != 0) {       /* we do want stat() here */
                /* Stat just set errno.  We don't have to */
                return -1;
        }

        synch_process_alive = 1;
        switch (cpid = fork()) {

        case -1:                /* Error in fork() */
                return (-1);    /* Errno is set already */

        case 0:         /* Child process */
                fd = sys_open("/dev/null", O_RDWR);
                if (fd >= 0) {
                        if (fd != STDIN_FILENO)
                                dup2(fd, STDIN_FILENO);
                        if (fd != STDOUT_FILENO)
                                dup2(fd, STDOUT_FILENO);
                        if (fd != STDERR_FILENO)
                                dup2(fd, STDERR_FILENO);
                }
                execl("/bin/rmdir", "rmdir", dpath, (char *)0);
                _exit(-1);      /* Can't exec /bin/mkdir */

        default:                /* Parent process */
                wait_for_termination(cpid);
        }

        if (synch_process_death != 0 || synch_process_retcode != 0) {
                errno = EIO;    /* We don't know why, but */
                return -1;      /* /bin/rmdir failed */
        }

        return 0;
}
#endif                          /* !HAVE_RMDIR */
\f
/************************************************************************/
/*                            Misc. SunOS crap                          */
/************************************************************************/

#ifdef USE_DL_STUBS

/* These are included on Sunos 4.1 when we do not use shared libraries.
   X11 libraries may refer to these functions but (we hope) do not
   actually call them.  */

void *dlopen(void)
{
        return 0;
}

void *dlsym(void)
{
        return 0;
}

int dlclose(void)
{
        return -1;
}

#endif                          /* USE_DL_STUBS */

\f
/* big dirname magic */

#if !defined(HAVE_DIRNAME)
/* some coreutils borrows here */
void
x__dirname(restrict char *res, const char *file, size_t len);
{
        /* assumes res is malloc'd of size LEN (and >= xstrlen(file)) */
        size_t file_len = xstrlen(file);
        size_t offs = x__dirlen(file, file_len);
        int append_dot = (offs == 0);

        xmemcpy(dir, file, offs);
        if (append_dot)
                res[offs++] = '.';
        res[offs] = '\0';
        return res;
}
#endif  /* !HAVE_DIRNAME */

/* sysdep.c ends here */