buf_write(
    buf_T	    *buf,
    char_u	    *fname,
    char_u	    *sfname,
    linenr_T	    start,
    linenr_T	    end,
    exarg_T	    *eap,		/* for forced 'ff' and 'fenc', can be
					   NULL! */
    int		    append,		/* append to the file */
    int		    forceit,
    int		    reset_changed,
    int		    filtering)
{
    int		    fd;
    char_u	    *backup = NULL;
    int		    backup_copy = FALSE; /* copy the original file? */
    int		    dobackup;
    char_u	    *ffname;
    char_u	    *wfname = NULL;	/* name of file to write to */
    char_u	    *s;
    char_u	    *ptr;
    char_u	    c;
    int		    len;
    linenr_T	    lnum;
    long	    nchars;
    char_u	    *errmsg = NULL;
    int		    errmsg_allocated = FALSE;
    char_u	    *errnum = NULL;
    char_u	    *buffer;
    char_u	    smallbuf[SMBUFSIZE];
    char_u	    *backup_ext;
    int		    bufsize;
    long	    perm;		    /* file permissions */
    int		    retval = OK;
    int		    newfile = FALSE;	    /* TRUE if file doesn't exist yet */
    int		    msg_save = msg_scroll;
    int		    overwriting;	    /* TRUE if writing over original */
    int		    no_eol = FALSE;	    /* no end-of-line written */
    int		    device = FALSE;	    /* writing to a device */
    stat_T	    st_old;
    int		    prev_got_int = got_int;
    int		    checking_conversion;
    int		    file_readonly = FALSE;  /* overwritten file is read-only */
    static char	    *err_readonly = "is read-only (cannot override: \"W\" in 'cpoptions')";
#if defined(UNIX)			    /*XXX fix me sometime? */
    int		    made_writable = FALSE;  /* 'w' bit has been set */
#endif
					/* writing everything */
    int		    whole = (start == 1 && end == buf->b_ml.ml_line_count);
#ifdef FEAT_AUTOCMD
    linenr_T	    old_line_count = buf->b_ml.ml_line_count;
#endif
    int		    attr;
    int		    fileformat;
    int		    write_bin;
    struct bw_info  write_info;		/* info for buf_write_bytes() */
#ifdef FEAT_MBYTE
    int		    converted = FALSE;
    int		    notconverted = FALSE;
    char_u	    *fenc;		/* effective 'fileencoding' */
    char_u	    *fenc_tofree = NULL; /* allocated "fenc" */
#endif
#ifdef HAS_BW_FLAGS
    int		    wb_flags = 0;
#endif
#ifdef HAVE_ACL
    vim_acl_T	    acl = NULL;		/* ACL copied from original file to
					   backup or new file */
#endif
#ifdef FEAT_PERSISTENT_UNDO
    int		    write_undo_file = FALSE;
    context_sha256_T sha_ctx;
#endif
    unsigned int    bkc = get_bkc_value(buf);

    if (fname == NULL || *fname == NUL)	/* safety check */
	return FAIL;
    if (buf->b_ml.ml_mfp == NULL)
    {
	/* This can happen during startup when there is a stray "w" in the
	 * vimrc file. */
	EMSG(_(e_emptybuf));
	return FAIL;
    }

    /*
     * Disallow writing from .exrc and .vimrc in current directory for
     * security reasons.
     */
    if (check_secure())
	return FAIL;

    /* Avoid a crash for a long name. */
    if (STRLEN(fname) >= MAXPATHL)
    {
	EMSG(_(e_longname));
	return FAIL;
    }

#ifdef FEAT_MBYTE
    /* must init bw_conv_buf and bw_iconv_fd before jumping to "fail" */
    write_info.bw_conv_buf = NULL;
    write_info.bw_conv_error = FALSE;
    write_info.bw_conv_error_lnum = 0;
    write_info.bw_restlen = 0;
# ifdef USE_ICONV
    write_info.bw_iconv_fd = (iconv_t)-1;
# endif
#endif
#ifdef FEAT_CRYPT
    write_info.bw_buffer = buf;
#endif

    /* After writing a file changedtick changes but we don't want to display
     * the line. */
    ex_no_reprint = TRUE;

    /*
     * If there is no file name yet, use the one for the written file.
     * BF_NOTEDITED is set to reflect this (in case the write fails).
     * Don't do this when the write is for a filter command.
     * Don't do this when appending.
     * Only do this when 'cpoptions' contains the 'F' flag.
     */
    if (buf->b_ffname == NULL
	    && reset_changed
	    && whole
	    && buf == curbuf
#ifdef FEAT_QUICKFIX
	    && !bt_nofile(buf)
#endif
	    && !filtering
	    && (!append || vim_strchr(p_cpo, CPO_FNAMEAPP) != NULL)
	    && vim_strchr(p_cpo, CPO_FNAMEW) != NULL)
    {
	if (set_rw_fname(fname, sfname) == FAIL)
	    return FAIL;
	buf = curbuf;	    /* just in case autocmds made "buf" invalid */
    }

    if (sfname == NULL)
	sfname = fname;
    /*
     * For Unix: Use the short file name whenever possible.
     * Avoids problems with networks and when directory names are changed.
     * Don't do this for MS-DOS, a "cd" in a sub-shell may have moved us to
     * another directory, which we don't detect
     */
    ffname = fname;			    /* remember full fname */
#ifdef UNIX
    fname = sfname;
#endif

    if (buf->b_ffname != NULL && fnamecmp(ffname, buf->b_ffname) == 0)
	overwriting = TRUE;
    else
	overwriting = FALSE;

    if (exiting)
	settmode(TMODE_COOK);	    /* when exiting allow typeahead now */

    ++no_wait_return;		    /* don't wait for return yet */

    /*
     * Set '[ and '] marks to the lines to be written.
     */
    buf->b_op_start.lnum = start;
    buf->b_op_start.col = 0;
    buf->b_op_end.lnum = end;
    buf->b_op_end.col = 0;

#ifdef FEAT_AUTOCMD
    {
	aco_save_T	aco;
	int		buf_ffname = FALSE;
	int		buf_sfname = FALSE;
	int		buf_fname_f = FALSE;
	int		buf_fname_s = FALSE;
	int		did_cmd = FALSE;
	int		nofile_err = FALSE;
	int		empty_memline = (buf->b_ml.ml_mfp == NULL);
	bufref_T	bufref;

	/*
	 * Apply PRE autocommands.
	 * Set curbuf to the buffer to be written.
	 * Careful: The autocommands may call buf_write() recursively!
	 */
	if (ffname == buf->b_ffname)
	    buf_ffname = TRUE;
	if (sfname == buf->b_sfname)
	    buf_sfname = TRUE;
	if (fname == buf->b_ffname)
	    buf_fname_f = TRUE;
	if (fname == buf->b_sfname)
	    buf_fname_s = TRUE;

	/* set curwin/curbuf to buf and save a few things */
	aucmd_prepbuf(&aco, buf);
	set_bufref(&bufref, buf);

	if (append)
	{
	    if (!(did_cmd = apply_autocmds_exarg(EVENT_FILEAPPENDCMD,
					 sfname, sfname, FALSE, curbuf, eap)))
	    {
#ifdef FEAT_QUICKFIX
		if (overwriting && bt_nofile(curbuf))
		    nofile_err = TRUE;
		else
#endif
		    apply_autocmds_exarg(EVENT_FILEAPPENDPRE,
					  sfname, sfname, FALSE, curbuf, eap);
	    }
	}
	else if (filtering)
	{
	    apply_autocmds_exarg(EVENT_FILTERWRITEPRE,
					    NULL, sfname, FALSE, curbuf, eap);
	}
	else if (reset_changed && whole)
	{
	    int was_changed = curbufIsChanged();

	    did_cmd = apply_autocmds_exarg(EVENT_BUFWRITECMD,
					  sfname, sfname, FALSE, curbuf, eap);
	    if (did_cmd)
	    {
		if (was_changed && !curbufIsChanged())
		{
		    /* Written everything correctly and BufWriteCmd has reset
		     * 'modified': Correct the undo information so that an
		     * undo now sets 'modified'. */
		    u_unchanged(curbuf);
		    u_update_save_nr(curbuf);
		}
	    }
	    else
	    {
#ifdef FEAT_QUICKFIX
		if (overwriting && bt_nofile(curbuf))
		    nofile_err = TRUE;
		else
#endif
		    apply_autocmds_exarg(EVENT_BUFWRITEPRE,
					  sfname, sfname, FALSE, curbuf, eap);
	    }
	}
	else
	{
	    if (!(did_cmd = apply_autocmds_exarg(EVENT_FILEWRITECMD,
					 sfname, sfname, FALSE, curbuf, eap)))
	    {
#ifdef FEAT_QUICKFIX
		if (overwriting && bt_nofile(curbuf))
		    nofile_err = TRUE;
		else
#endif
		    apply_autocmds_exarg(EVENT_FILEWRITEPRE,
					  sfname, sfname, FALSE, curbuf, eap);
	    }
	}

	/* restore curwin/curbuf and a few other things */
	aucmd_restbuf(&aco);

	/*
	 * In three situations we return here and don't write the file:
	 * 1. the autocommands deleted or unloaded the buffer.
	 * 2. The autocommands abort script processing.
	 * 3. If one of the "Cmd" autocommands was executed.
	 */
	if (!bufref_valid(&bufref))
	    buf = NULL;
	if (buf == NULL || (buf->b_ml.ml_mfp == NULL && !empty_memline)
				       || did_cmd || nofile_err
#ifdef FEAT_EVAL
				       || aborting()
#endif
				       )
	{
	    --no_wait_return;
	    msg_scroll = msg_save;
	    if (nofile_err)
		EMSG(_("E676: No matching autocommands for acwrite buffer"));

	    if (nofile_err
#ifdef FEAT_EVAL
		    || aborting()
#endif
		    )
		/* An aborting error, interrupt or exception in the
		 * autocommands. */
		return FAIL;
	    if (did_cmd)
	    {
		if (buf == NULL)
		    /* The buffer was deleted.  We assume it was written
		     * (can't retry anyway). */
		    return OK;
		if (overwriting)
		{
		    /* Assume the buffer was written, update the timestamp. */
		    ml_timestamp(buf);
		    if (append)
			buf->b_flags &= ~BF_NEW;
		    else
			buf->b_flags &= ~BF_WRITE_MASK;
		}
		if (reset_changed && buf->b_changed && !append
			&& (overwriting || vim_strchr(p_cpo, CPO_PLUS) != NULL))
		    /* Buffer still changed, the autocommands didn't work
		     * properly. */
		    return FAIL;
		return OK;
	    }
#ifdef FEAT_EVAL
	    if (!aborting())
#endif
		EMSG(_("E203: Autocommands deleted or unloaded buffer to be written"));
	    return FAIL;
	}

	/*
	 * The autocommands may have changed the number of lines in the file.
	 * When writing the whole file, adjust the end.
	 * When writing part of the file, assume that the autocommands only
	 * changed the number of lines that are to be written (tricky!).
	 */
	if (buf->b_ml.ml_line_count != old_line_count)
	{
	    if (whole)						/* write all */
		end = buf->b_ml.ml_line_count;
	    else if (buf->b_ml.ml_line_count > old_line_count)	/* more lines */
		end += buf->b_ml.ml_line_count - old_line_count;
	    else						/* less lines */
	    {
		end -= old_line_count - buf->b_ml.ml_line_count;
		if (end < start)
		{
		    --no_wait_return;
		    msg_scroll = msg_save;
		    EMSG(_("E204: Autocommand changed number of lines in unexpected way"));
		    return FAIL;
		}
	    }
	}

	/*
	 * The autocommands may have changed the name of the buffer, which may
	 * be kept in fname, ffname and sfname.
	 */
	if (buf_ffname)
	    ffname = buf->b_ffname;
	if (buf_sfname)
	    sfname = buf->b_sfname;
	if (buf_fname_f)
	    fname = buf->b_ffname;
	if (buf_fname_s)
	    fname = buf->b_sfname;
    }
#endif

#ifdef FEAT_NETBEANS_INTG
    if (netbeans_active() && isNetbeansBuffer(buf))
    {
	if (whole)
	{
	    /*
	     * b_changed can be 0 after an undo, but we still need to write
	     * the buffer to NetBeans.
	     */
	    if (buf->b_changed || isNetbeansModified(buf))
	    {
		--no_wait_return;		/* may wait for return now */
		msg_scroll = msg_save;
		netbeans_save_buffer(buf);	/* no error checking... */
		return retval;
	    }
	    else
	    {
		errnum = (char_u *)"E656: ";
		errmsg = (char_u *)_("NetBeans disallows writes of unmodified buffers");
		buffer = NULL;
		goto fail;
	    }
	}
	else
	{
	    errnum = (char_u *)"E657: ";
	    errmsg = (char_u *)_("Partial writes disallowed for NetBeans buffers");
	    buffer = NULL;
	    goto fail;
	}
    }
#endif

    if (shortmess(SHM_OVER) && !exiting)
	msg_scroll = FALSE;	    /* overwrite previous file message */
    else
	msg_scroll = TRUE;	    /* don't overwrite previous file message */
    if (!filtering)
	filemess(buf,
#ifndef UNIX
		sfname,
#else
		fname,
#endif
		    (char_u *)"", 0);	/* show that we are busy */
    msg_scroll = FALSE;		    /* always overwrite the file message now */

    buffer = alloc(BUFSIZE);
    if (buffer == NULL)		    /* can't allocate big buffer, use small
				     * one (to be able to write when out of
				     * memory) */
    {
	buffer = smallbuf;
	bufsize = SMBUFSIZE;
    }
    else
	bufsize = BUFSIZE;

    /*
     * Get information about original file (if there is one).
     */
#if defined(UNIX)
    st_old.st_dev = 0;
    st_old.st_ino = 0;
    perm = -1;
    if (mch_stat((char *)fname, &st_old) < 0)
	newfile = TRUE;
    else
    {
	perm = st_old.st_mode;
	if (!S_ISREG(st_old.st_mode))		/* not a file */
	{
	    if (S_ISDIR(st_old.st_mode))
	    {
		errnum = (char_u *)"E502: ";
		errmsg = (char_u *)_("is a directory");
		goto fail;
	    }
	    if (mch_nodetype(fname) != NODE_WRITABLE)
	    {
		errnum = (char_u *)"E503: ";
		errmsg = (char_u *)_("is not a file or writable device");
		goto fail;
	    }
	    /* It's a device of some kind (or a fifo) which we can write to
	     * but for which we can't make a backup. */
	    device = TRUE;
	    newfile = TRUE;
	    perm = -1;
	}
    }
#else /* !UNIX */
    /*
     * Check for a writable device name.
     */
    c = mch_nodetype(fname);
    if (c == NODE_OTHER)
    {
	errnum = (char_u *)"E503: ";
	errmsg = (char_u *)_("is not a file or writable device");
	goto fail;
    }
    if (c == NODE_WRITABLE)
    {
# if defined(MSWIN)
	/* MS-Windows allows opening a device, but we will probably get stuck
	 * trying to write to it.  */
	if (!p_odev)
	{
	    errnum = (char_u *)"E796: ";
	    errmsg = (char_u *)_("writing to device disabled with 'opendevice' option");
	    goto fail;
	}
# endif
	device = TRUE;
	newfile = TRUE;
	perm = -1;
    }
    else
    {
	perm = mch_getperm(fname);
	if (perm < 0)
	    newfile = TRUE;
	else if (mch_isdir(fname))
	{
	    errnum = (char_u *)"E502: ";
	    errmsg = (char_u *)_("is a directory");
	    goto fail;
	}
	if (overwriting)
	    (void)mch_stat((char *)fname, &st_old);
    }
#endif /* !UNIX */

    if (!device && !newfile)
    {
	/*
	 * Check if the file is really writable (when renaming the file to
	 * make a backup we won't discover it later).
	 */
	file_readonly = check_file_readonly(fname, (int)perm);

	if (!forceit && file_readonly)
	{
	    if (vim_strchr(p_cpo, CPO_FWRITE) != NULL)
	    {
		errnum = (char_u *)"E504: ";
		errmsg = (char_u *)_(err_readonly);
	    }
	    else
	    {
		errnum = (char_u *)"E505: ";
		errmsg = (char_u *)_("is read-only (add ! to override)");
	    }
	    goto fail;
	}

	/*
	 * Check if the timestamp hasn't changed since reading the file.
	 */
	if (overwriting)
	{
	    retval = check_mtime(buf, &st_old);
	    if (retval == FAIL)
		goto fail;
	}
    }

#ifdef HAVE_ACL
    /*
     * For systems that support ACL: get the ACL from the original file.
     */
    if (!newfile)
	acl = mch_get_acl(fname);
#endif

    /*
     * If 'backupskip' is not empty, don't make a backup for some files.
     */
    dobackup = (p_wb || p_bk || *p_pm != NUL);
#ifdef FEAT_WILDIGN
    if (dobackup && *p_bsk != NUL && match_file_list(p_bsk, sfname, ffname))
	dobackup = FALSE;
#endif

    /*
     * Save the value of got_int and reset it.  We don't want a previous
     * interruption cancel writing, only hitting CTRL-C while writing should
     * abort it.
     */
    prev_got_int = got_int;
    got_int = FALSE;

    /* Mark the buffer as 'being saved' to prevent changed buffer warnings */
    buf->b_saving = TRUE;

    /*
     * If we are not appending or filtering, the file exists, and the
     * 'writebackup', 'backup' or 'patchmode' option is set, need a backup.
     * When 'patchmode' is set also make a backup when appending.
     *
     * Do not make any backup, if 'writebackup' and 'backup' are both switched
     * off.  This helps when editing large files on almost-full disks.
     */
    if (!(append && *p_pm == NUL) && !filtering && perm >= 0 && dobackup)
    {
#if defined(UNIX) || defined(WIN32)
	stat_T	    st;
#endif

	if ((bkc & BKC_YES) || append)	/* "yes" */
	    backup_copy = TRUE;
#if defined(UNIX) || defined(WIN32)
	else if ((bkc & BKC_AUTO))	/* "auto" */
	{
	    int		i;

# ifdef UNIX
	    /*
	     * Don't rename the file when:
	     * - it's a hard link
	     * - it's a symbolic link
	     * - we don't have write permission in the directory
	     * - we can't set the owner/group of the new file
	     */
	    if (st_old.st_nlink > 1
		    || mch_lstat((char *)fname, &st) < 0
		    || st.st_dev != st_old.st_dev
		    || st.st_ino != st_old.st_ino
#  ifndef HAVE_FCHOWN
		    || st.st_uid != st_old.st_uid
		    || st.st_gid != st_old.st_gid
#  endif
		    )
		backup_copy = TRUE;
	    else
# else
#  ifdef WIN32
	    /* On NTFS file systems hard links are possible. */
	    if (mch_is_linked(fname))
		backup_copy = TRUE;
	    else
#  endif
# endif
	    {
		/*
		 * Check if we can create a file and set the owner/group to
		 * the ones from the original file.
		 * First find a file name that doesn't exist yet (use some
		 * arbitrary numbers).
		 */
		STRCPY(IObuff, fname);
		for (i = 4913; ; i += 123)
		{
		    sprintf((char *)gettail(IObuff), "%d", i);
		    if (mch_lstat((char *)IObuff, &st) < 0)
			break;
		}
		fd = mch_open((char *)IObuff,
				    O_CREAT|O_WRONLY|O_EXCL|O_NOFOLLOW, perm);
		if (fd < 0)	/* can't write in directory */
		    backup_copy = TRUE;
		else
		{
# ifdef UNIX
#  ifdef HAVE_FCHOWN
		    ignored = fchown(fd, st_old.st_uid, st_old.st_gid);
#  endif
		    if (mch_stat((char *)IObuff, &st) < 0
			    || st.st_uid != st_old.st_uid
			    || st.st_gid != st_old.st_gid
			    || (long)st.st_mode != perm)
			backup_copy = TRUE;
# endif
		    /* Close the file before removing it, on MS-Windows we
		     * can't delete an open file. */
		    close(fd);
		    mch_remove(IObuff);
# ifdef MSWIN
		    /* MS-Windows may trigger a virus scanner to open the
		     * file, we can't delete it then.  Keep trying for half a
		     * second. */
		    {
			int try;

			for (try = 0; try < 10; ++try)
			{
			    if (mch_lstat((char *)IObuff, &st) < 0)
				break;
			    ui_delay(50L, TRUE);  /* wait 50 msec */
			    mch_remove(IObuff);
			}
		    }
# endif
		}
	    }
	}

	/*
	 * Break symlinks and/or hardlinks if we've been asked to.
	 */
	if ((bkc & BKC_BREAKSYMLINK) || (bkc & BKC_BREAKHARDLINK))
	{
# ifdef UNIX
	    int	lstat_res;

	    lstat_res = mch_lstat((char *)fname, &st);

	    /* Symlinks. */
	    if ((bkc & BKC_BREAKSYMLINK)
		    && lstat_res == 0
		    && st.st_ino != st_old.st_ino)
		backup_copy = FALSE;

	    /* Hardlinks. */
	    if ((bkc & BKC_BREAKHARDLINK)
		    && st_old.st_nlink > 1
		    && (lstat_res != 0 || st.st_ino == st_old.st_ino))
		backup_copy = FALSE;
# else
#  if defined(WIN32)
	    /* Symlinks. */
	    if ((bkc & BKC_BREAKSYMLINK) && mch_is_symbolic_link(fname))
		backup_copy = FALSE;

	    /* Hardlinks. */
	    if ((bkc & BKC_BREAKHARDLINK) && mch_is_hard_link(fname))
		backup_copy = FALSE;
#  endif
# endif
	}

#endif

	/* make sure we have a valid backup extension to use */
	if (*p_bex == NUL)
	    backup_ext = (char_u *)".bak";
	else
	    backup_ext = p_bex;

	if (backup_copy
		&& (fd = mch_open((char *)fname, O_RDONLY | O_EXTRA, 0)) >= 0)
	{
	    int		bfd;
	    char_u	*copybuf, *wp;
	    int		some_error = FALSE;
	    stat_T	st_new;
	    char_u	*dirp;
	    char_u	*rootname;
#if defined(UNIX)
	    int		did_set_shortname;
#endif

	    copybuf = alloc(BUFSIZE + 1);
	    if (copybuf == NULL)
	    {
		some_error = TRUE;	    /* out of memory */
		goto nobackup;
	    }

	    /*
	     * Try to make the backup in each directory in the 'bdir' option.
	     *
	     * Unix semantics has it, that we may have a writable file,
	     * that cannot be recreated with a simple open(..., O_CREAT, ) e.g:
	     *  - the directory is not writable,
	     *  - the file may be a symbolic link,
	     *  - the file may belong to another user/group, etc.
	     *
	     * For these reasons, the existing writable file must be truncated
	     * and reused. Creation of a backup COPY will be attempted.
	     */
	    dirp = p_bdir;
	    while (*dirp)
	    {
#ifdef UNIX
		st_new.st_ino = 0;
		st_new.st_dev = 0;
		st_new.st_gid = 0;
#endif

		/*
		 * Isolate one directory name, using an entry in 'bdir'.
		 */
		(void)copy_option_part(&dirp, copybuf, BUFSIZE, ",");
		rootname = get_file_in_dir(fname, copybuf);
		if (rootname == NULL)
		{
		    some_error = TRUE;	    /* out of memory */
		    goto nobackup;
		}

#if defined(UNIX)
		did_set_shortname = FALSE;
#endif

		/*
		 * May try twice if 'shortname' not set.
		 */
		for (;;)
		{
		    /*
		     * Make backup file name.
		     */
		    backup = buf_modname((buf->b_p_sn || buf->b_shortname),
						 rootname, backup_ext, FALSE);
		    if (backup == NULL)
		    {
			vim_free(rootname);
			some_error = TRUE;		/* out of memory */
			goto nobackup;
		    }

		    /*
		     * Check if backup file already exists.
		     */
		    if (mch_stat((char *)backup, &st_new) >= 0)
		    {
#ifdef UNIX
			/*
			 * Check if backup file is same as original file.
			 * May happen when modname() gave the same file back.
			 * E.g. silly link, or file name-length reached.
			 * If we don't check here, we either ruin the file
			 * when copying or erase it after writing. jw.
			 */
			if (st_new.st_dev == st_old.st_dev
					    && st_new.st_ino == st_old.st_ino)
			{
			    vim_free(backup);
			    backup = NULL;	/* no backup file to delete */
			    /*
			     * may try again with 'shortname' set
			     */
			    if (!(buf->b_shortname || buf->b_p_sn))
			    {
				buf->b_shortname = TRUE;
				did_set_shortname = TRUE;
				continue;
			    }
				/* setting shortname didn't help */
			    if (did_set_shortname)
				buf->b_shortname = FALSE;
			    break;
			}
#endif

			/*
			 * If we are not going to keep the backup file, don't
			 * delete an existing one, try to use another name.
			 * Change one character, just before the extension.
			 */
			if (!p_bk)
			{
			    wp = backup + STRLEN(backup) - 1
							 - STRLEN(backup_ext);
			    if (wp < backup)	/* empty file name ??? */
				wp = backup;
			    *wp = 'z';
			    while (*wp > 'a'
				    && mch_stat((char *)backup, &st_new) >= 0)
				--*wp;
			    /* They all exist??? Must be something wrong. */
			    if (*wp == 'a')
			    {
				vim_free(backup);
				backup = NULL;
			    }
			}
		    }
		    break;
		}
		vim_free(rootname);

		/*
		 * Try to create the backup file
		 */
		if (backup != NULL)
		{
		    /* remove old backup, if present */
		    mch_remove(backup);
		    /* Open with O_EXCL to avoid the file being created while
		     * we were sleeping (symlink hacker attack?) */
		    bfd = mch_open((char *)backup,
				O_WRONLY|O_CREAT|O_EXTRA|O_EXCL|O_NOFOLLOW,
								 perm & 0777);
		    if (bfd < 0)
		    {
			vim_free(backup);
			backup = NULL;
		    }
		    else
		    {
			/* set file protection same as original file, but
			 * strip s-bit */
			(void)mch_setperm(backup, perm & 0777);

#ifdef UNIX
			/*
			 * Try to set the group of the backup same as the
			 * original file. If this fails, set the protection
			 * bits for the group same as the protection bits for
			 * others.
			 */
			if (st_new.st_gid != st_old.st_gid
# ifdef HAVE_FCHOWN  /* sequent-ptx lacks fchown() */
				&& fchown(bfd, (uid_t)-1, st_old.st_gid) != 0
# endif
						)
			    mch_setperm(backup,
					  (perm & 0707) | ((perm & 07) << 3));
# if defined(HAVE_SELINUX) || defined(HAVE_SMACK)
			mch_copy_sec(fname, backup);
# endif
#endif

			/*
			 * copy the file.
			 */
			write_info.bw_fd = bfd;
			write_info.bw_buf = copybuf;
#ifdef HAS_BW_FLAGS
			write_info.bw_flags = FIO_NOCONVERT;
#endif
			while ((write_info.bw_len = read_eintr(fd, copybuf,
								BUFSIZE)) > 0)
			{
			    if (buf_write_bytes(&write_info) == FAIL)
			    {
				errmsg = (char_u *)_("E506: Can't write to backup file (add ! to override)");
				break;
			    }
			    ui_breakcheck();
			    if (got_int)
			    {
				errmsg = (char_u *)_(e_interr);
				break;
			    }
			}

			if (close(bfd) < 0 && errmsg == NULL)
			    errmsg = (char_u *)_("E507: Close error for backup file (add ! to override)");
			if (write_info.bw_len < 0)
			    errmsg = (char_u *)_("E508: Can't read file for backup (add ! to override)");
#ifdef UNIX
			set_file_time(backup, st_old.st_atime, st_old.st_mtime);
#endif
#ifdef HAVE_ACL
			mch_set_acl(backup, acl);
#endif
#if defined(HAVE_SELINUX) || defined(HAVE_SMACK)
			mch_copy_sec(fname, backup);
#endif
			break;
		    }
		}
	    }
    nobackup:
	    close(fd);		/* ignore errors for closing read file */
	    vim_free(copybuf);

	    if (backup == NULL && errmsg == NULL)
		errmsg = (char_u *)_("E509: Cannot create backup file (add ! to override)");
	    /* ignore errors when forceit is TRUE */
	    if ((some_error || errmsg != NULL) && !forceit)
	    {
		retval = FAIL;
		goto fail;
	    }
	    errmsg = NULL;
	}
	else
	{
	    char_u	*dirp;
	    char_u	*p;
	    char_u	*rootname;

	    /*
	     * Make a backup by renaming the original file.
	     */
	    /*
	     * If 'cpoptions' includes the "W" flag, we don't want to
	     * overwrite a read-only file.  But rename may be possible
	     * anyway, thus we need an extra check here.
	     */
	    if (file_readonly && vim_strchr(p_cpo, CPO_FWRITE) != NULL)
	    {
		errnum = (char_u *)"E504: ";
		errmsg = (char_u *)_(err_readonly);
		goto fail;
	    }

	    /*
	     *
	     * Form the backup file name - change path/fo.o.h to
	     * path/fo.o.h.bak Try all directories in 'backupdir', first one
	     * that works is used.
	     */
	    dirp = p_bdir;
	    while (*dirp)
	    {
		/*
		 * Isolate one directory name and make the backup file name.
		 */
		(void)copy_option_part(&dirp, IObuff, IOSIZE, ",");
		rootname = get_file_in_dir(fname, IObuff);
		if (rootname == NULL)
		    backup = NULL;
		else
		{
		    backup = buf_modname((buf->b_p_sn || buf->b_shortname),
						 rootname, backup_ext, FALSE);
		    vim_free(rootname);
		}

		if (backup != NULL)
		{
		    /*
		     * If we are not going to keep the backup file, don't
		     * delete an existing one, try to use another name.
		     * Change one character, just before the extension.
		     */
		    if (!p_bk && mch_getperm(backup) >= 0)
		    {
			p = backup + STRLEN(backup) - 1 - STRLEN(backup_ext);
			if (p < backup)	/* empty file name ??? */
			    p = backup;
			*p = 'z';
			while (*p > 'a' && mch_getperm(backup) >= 0)
			    --*p;
			/* They all exist??? Must be something wrong! */
			if (*p == 'a')
			{
			    vim_free(backup);
			    backup = NULL;
			}
		    }
		}
		if (backup != NULL)
		{
		    /*
		     * Delete any existing backup and move the current version
		     * to the backup.	For safety, we don't remove the backup
		     * until the write has finished successfully. And if the
		     * 'backup' option is set, leave it around.
		     */
		    /*
		     * If the renaming of the original file to the backup file
		     * works, quit here.
		     */
		    if (vim_rename(fname, backup) == 0)
			break;

		    vim_free(backup);   /* don't do the rename below */
		    backup = NULL;
		}
	    }
	    if (backup == NULL && !forceit)
	    {
		errmsg = (char_u *)_("E510: Can't make backup file (add ! to override)");
		goto fail;
	    }
	}
    }

#if defined(UNIX)
    /* When using ":w!" and the file was read-only: make it writable */
    if (forceit && perm >= 0 && !(perm & 0200) && st_old.st_uid == getuid()
				     && vim_strchr(p_cpo, CPO_FWRITE) == NULL)
    {
	perm |= 0200;
	(void)mch_setperm(fname, perm);
	made_writable = TRUE;
    }
#endif

    /* When using ":w!" and writing to the current file, 'readonly' makes no
     * sense, reset it, unless 'Z' appears in 'cpoptions'.  */
    if (forceit && overwriting && vim_strchr(p_cpo, CPO_KEEPRO) == NULL)
    {
	buf->b_p_ro = FALSE;
#ifdef FEAT_TITLE
	need_maketitle = TRUE;	    /* set window title later */
#endif
	status_redraw_all();	    /* redraw status lines later */
    }

    if (end > buf->b_ml.ml_line_count)
	end = buf->b_ml.ml_line_count;
    if (buf->b_ml.ml_flags & ML_EMPTY)
	start = end + 1;

    /*
     * If the original file is being overwritten, there is a small chance that
     * we crash in the middle of writing. Therefore the file is preserved now.
     * This makes all block numbers positive so that recovery does not need
     * the original file.
     * Don't do this if there is a backup file and we are exiting.
     */
    if (reset_changed && !newfile && overwriting
					      && !(exiting && backup != NULL))
    {
	ml_preserve(buf, FALSE);
	if (got_int)
	{
	    errmsg = (char_u *)_(e_interr);
	    goto restore_backup;
	}
    }

#ifdef VMS
    vms_remove_version(fname); /* remove version */
#endif
    /* Default: write the file directly.  May write to a temp file for
     * multi-byte conversion. */
    wfname = fname;

#ifdef FEAT_MBYTE
    /* Check for forced 'fileencoding' from "++opt=val" argument. */
    if (eap != NULL && eap->force_enc != 0)
    {
	fenc = eap->cmd + eap->force_enc;
	fenc = enc_canonize(fenc);
	fenc_tofree = fenc;
    }
    else
	fenc = buf->b_p_fenc;

    /*
     * Check if the file needs to be converted.
     */
    converted = need_conversion(fenc);

    /*
     * Check if UTF-8 to UCS-2/4 or Latin1 conversion needs to be done.  Or
     * Latin1 to Unicode conversion.  This is handled in buf_write_bytes().
     * Prepare the flags for it and allocate bw_conv_buf when needed.
     */
    if (converted && (enc_utf8 || STRCMP(p_enc, "latin1") == 0))
    {
	wb_flags = get_fio_flags(fenc);
	if (wb_flags & (FIO_UCS2 | FIO_UCS4 | FIO_UTF16 | FIO_UTF8))
	{
	    /* Need to allocate a buffer to translate into. */
	    if (wb_flags & (FIO_UCS2 | FIO_UTF16 | FIO_UTF8))
		write_info.bw_conv_buflen = bufsize * 2;
	    else /* FIO_UCS4 */
		write_info.bw_conv_buflen = bufsize * 4;
	    write_info.bw_conv_buf
			   = lalloc((long_u)write_info.bw_conv_buflen, TRUE);
	    if (write_info.bw_conv_buf == NULL)
		end = 0;
	}
    }

# ifdef WIN3264
    if (converted && wb_flags == 0 && (wb_flags = get_win_fio_flags(fenc)) != 0)
    {
	/* Convert UTF-8 -> UCS-2 and UCS-2 -> DBCS.  Worst-case * 4: */
	write_info.bw_conv_buflen = bufsize * 4;
	write_info.bw_conv_buf
			    = lalloc((long_u)write_info.bw_conv_buflen, TRUE);
	if (write_info.bw_conv_buf == NULL)
	    end = 0;
    }
# endif

# ifdef MACOS_CONVERT
    if (converted && wb_flags == 0 && (wb_flags = get_mac_fio_flags(fenc)) != 0)
    {
	write_info.bw_conv_buflen = bufsize * 3;
	write_info.bw_conv_buf
			    = lalloc((long_u)write_info.bw_conv_buflen, TRUE);
	if (write_info.bw_conv_buf == NULL)
	    end = 0;
    }
# endif

# if defined(FEAT_EVAL) || defined(USE_ICONV)
    if (converted && wb_flags == 0)
    {
#  ifdef USE_ICONV
	/*
	 * Use iconv() conversion when conversion is needed and it's not done
	 * internally.
	 */
	write_info.bw_iconv_fd = (iconv_t)my_iconv_open(fenc,
					enc_utf8 ? (char_u *)"utf-8" : p_enc);
	if (write_info.bw_iconv_fd != (iconv_t)-1)
	{
	    /* We're going to use iconv(), allocate a buffer to convert in. */
	    write_info.bw_conv_buflen = bufsize * ICONV_MULT;
	    write_info.bw_conv_buf
			   = lalloc((long_u)write_info.bw_conv_buflen, TRUE);
	    if (write_info.bw_conv_buf == NULL)
		end = 0;
	    write_info.bw_first = TRUE;
	}
#   ifdef FEAT_EVAL
	else
#   endif
#  endif

#  ifdef FEAT_EVAL
	    /*
	     * When the file needs to be converted with 'charconvert' after
	     * writing, write to a temp file instead and let the conversion
	     * overwrite the original file.
	     */
	    if (*p_ccv != NUL)
	    {
		wfname = vim_tempname('w', FALSE);
		if (wfname == NULL)	/* Can't write without a tempfile! */
		{
		    errmsg = (char_u *)_("E214: Can't find temp file for writing");
		    goto restore_backup;
		}
	    }
#  endif
    }
# endif
    if (converted && wb_flags == 0
#  ifdef USE_ICONV
	    && write_info.bw_iconv_fd == (iconv_t)-1
#  endif
#  ifdef FEAT_EVAL
	    && wfname == fname
#  endif
	    )
    {
	if (!forceit)
	{
	    errmsg = (char_u *)_("E213: Cannot convert (add ! to write without conversion)");
	    goto restore_backup;
	}
	notconverted = TRUE;
    }
#endif

    /*
     * If conversion is taking place, we may first pretend to write and check
     * for conversion errors.  Then loop again to write for real.
     * When not doing conversion this writes for real right away.
     */
    for (checking_conversion = TRUE; ; checking_conversion = FALSE)
    {
	/*
	 * There is no need to check conversion when:
	 * - there is no conversion
	 * - we make a backup file, that can be restored in case of conversion
	 *   failure.
	 */
#ifdef FEAT_MBYTE
	if (!converted || dobackup)
#endif
	    checking_conversion = FALSE;

	if (checking_conversion)
	{
	    /* Make sure we don't write anything. */
	    fd = -1;
	    write_info.bw_fd = fd;
	}
	else
	{
	    /*
	     * Open the file "wfname" for writing.
	     * We may try to open the file twice: If we can't write to the file
	     * and forceit is TRUE we delete the existing file and try to
	     * create a new one. If this still fails we may have lost the
	     * original file!  (this may happen when the user reached his
	     * quotum for number of files).
	     * Appending will fail if the file does not exist and forceit is
	     * FALSE.
	     */
	    while ((fd = mch_open((char *)wfname, O_WRONLY | O_EXTRA | (append
				? (forceit ? (O_APPEND | O_CREAT) : O_APPEND)
				: (O_CREAT | O_TRUNC))
				, perm < 0 ? 0666 : (perm & 0777))) < 0)
	    {
		/*
		 * A forced write will try to create a new file if the old one
		 * is still readonly. This may also happen when the directory
		 * is read-only. In that case the mch_remove() will fail.
		 */
		if (errmsg == NULL)
		{
#ifdef UNIX
		    stat_T	st;

		    /* Don't delete the file when it's a hard or symbolic link.
		     */
		    if ((!newfile && st_old.st_nlink > 1)
			    || (mch_lstat((char *)fname, &st) == 0
				&& (st.st_dev != st_old.st_dev
				    || st.st_ino != st_old.st_ino)))
			errmsg = (char_u *)_("E166: Can't open linked file for writing");
		    else
#endif
		    {
			errmsg = (char_u *)_("E212: Can't open file for writing");
			if (forceit && vim_strchr(p_cpo, CPO_FWRITE) == NULL
								  && perm >= 0)
			{
#ifdef UNIX
			    /* we write to the file, thus it should be marked
			       writable after all */
			    if (!(perm & 0200))
				made_writable = TRUE;
			    perm |= 0200;
			    if (st_old.st_uid != getuid()
						  || st_old.st_gid != getgid())
				perm &= 0777;
#endif
			    if (!append)  /* don't remove when appending */
				mch_remove(wfname);
			    continue;
			}
		    }
		}

restore_backup:
		{
		    stat_T	st;

		    /*
		     * If we failed to open the file, we don't need a backup.
		     * Throw it away.  If we moved or removed the original file
		     * try to put the backup in its place.
		     */
		    if (backup != NULL && wfname == fname)
		    {
			if (backup_copy)
			{
			    /*
			     * There is a small chance that we removed the
			     * original, try to move the copy in its place.
			     * This may not work if the vim_rename() fails.
			     * In that case we leave the copy around.
			     */
			    /* If file does not exist, put the copy in its
			     * place */
			    if (mch_stat((char *)fname, &st) < 0)
				vim_rename(backup, fname);
			    /* if original file does exist throw away the copy
			     */
			    if (mch_stat((char *)fname, &st) >= 0)
				mch_remove(backup);
			}
			else
			{
			    /* try to put the original file back */
			    vim_rename(backup, fname);
			}
		    }

		    /* if original file no longer exists give an extra warning
		     */
		    if (!newfile && mch_stat((char *)fname, &st) < 0)
			end = 0;
		}

#ifdef FEAT_MBYTE
		if (wfname != fname)
		    vim_free(wfname);
#endif
		goto fail;
	    }
	    write_info.bw_fd = fd;

#if defined(WIN3264)
	    if (backup != NULL && overwriting && !append)
	    {
		if (backup_copy)
		    (void)mch_copy_file_attribute(wfname, backup);
		else
		    (void)mch_copy_file_attribute(backup, wfname);
	    }

	    if (!overwriting && !append)
	    {
		if (buf->b_ffname != NULL)
		    (void)mch_copy_file_attribute(buf->b_ffname, wfname);
		/* Should copy resource fork */
	    }
#endif

#ifdef FEAT_CRYPT
	    if (*buf->b_p_key != NUL && !filtering)
	    {
		char_u		*header;
		int		header_len;

		buf->b_cryptstate = crypt_create_for_writing(
						      crypt_get_method_nr(buf),
					   buf->b_p_key, &header, &header_len);
		if (buf->b_cryptstate == NULL || header == NULL)
		    end = 0;
		else
		{
		    /* Write magic number, so that Vim knows how this file is
		     * encrypted when reading it back. */
		    write_info.bw_buf = header;
		    write_info.bw_len = header_len;
		    write_info.bw_flags = FIO_NOCONVERT;
		    if (buf_write_bytes(&write_info) == FAIL)
			end = 0;
		    wb_flags |= FIO_ENCRYPTED;
		    vim_free(header);
		}
	    }
#endif
	}
	errmsg = NULL;

	write_info.bw_buf = buffer;
	nchars = 0;

	/* use "++bin", "++nobin" or 'binary' */
	if (eap != NULL && eap->force_bin != 0)
	    write_bin = (eap->force_bin == FORCE_BIN);
	else
	    write_bin = buf->b_p_bin;

#ifdef FEAT_MBYTE
	/*
	 * The BOM is written just after the encryption magic number.
	 * Skip it when appending and the file already existed, the BOM only
	 * makes sense at the start of the file.
	 */
	if (buf->b_p_bomb && !write_bin && (!append || perm < 0))
	{
	    write_info.bw_len = make_bom(buffer, fenc);
	    if (write_info.bw_len > 0)
	    {
		/* don't convert, do encryption */
		write_info.bw_flags = FIO_NOCONVERT | wb_flags;
		if (buf_write_bytes(&write_info) == FAIL)
		    end = 0;
		else
		    nchars += write_info.bw_len;
	    }
	}
	write_info.bw_start_lnum = start;
#endif

#ifdef FEAT_PERSISTENT_UNDO
	write_undo_file = (buf->b_p_udf
			    && overwriting
			    && !append
			    && !filtering
			    && reset_changed
			    && !checking_conversion);
	if (write_undo_file)
	    /* Prepare for computing the hash value of the text. */
	    sha256_start(&sha_ctx);
#endif

	write_info.bw_len = bufsize;
#ifdef HAS_BW_FLAGS
	write_info.bw_flags = wb_flags;
#endif
	fileformat = get_fileformat_force(buf, eap);
	s = buffer;
	len = 0;
	for (lnum = start; lnum <= end; ++lnum)
	{
	    /*
	     * The next while loop is done once for each character written.
	     * Keep it fast!
	     */
	    ptr = ml_get_buf(buf, lnum, FALSE) - 1;
#ifdef FEAT_PERSISTENT_UNDO
	    if (write_undo_file)
		sha256_update(&sha_ctx, ptr + 1,
					      (UINT32_T)(STRLEN(ptr + 1) + 1));
#endif
	    while ((c = *++ptr) != NUL)
	    {
		if (c == NL)
		    *s = NUL;		/* replace newlines with NULs */
		else if (c == CAR && fileformat == EOL_MAC)
		    *s = NL;		/* Mac: replace CRs with NLs */
		else
		    *s = c;
		++s;
		if (++len != bufsize)
		    continue;
		if (buf_write_bytes(&write_info) == FAIL)
		{
		    end = 0;		/* write error: break loop */
		    break;
		}
		nchars += bufsize;
		s = buffer;
		len = 0;
#ifdef FEAT_MBYTE
		write_info.bw_start_lnum = lnum;
#endif
	    }
	    /* write failed or last line has no EOL: stop here */
	    if (end == 0
		    || (lnum == end
			&& (write_bin || !buf->b_p_fixeol)
			&& (lnum == buf->b_no_eol_lnum
			    || (lnum == buf->b_ml.ml_line_count
							   && !buf->b_p_eol))))
	    {
		++lnum;			/* written the line, count it */
		no_eol = TRUE;
		break;
	    }
	    if (fileformat == EOL_UNIX)
		*s++ = NL;
	    else
	    {
		*s++ = CAR;		    /* EOL_MAC or EOL_DOS: write CR */
		if (fileformat == EOL_DOS)  /* write CR-NL */
		{
		    if (++len == bufsize)
		    {
			if (buf_write_bytes(&write_info) == FAIL)
			{
			    end = 0;	/* write error: break loop */
			    break;
			}
			nchars += bufsize;
			s = buffer;
			len = 0;
		    }
		    *s++ = NL;
		}
	    }
	    if (++len == bufsize && end)
	    {
		if (buf_write_bytes(&write_info) == FAIL)
		{
		    end = 0;		/* write error: break loop */
		    break;
		}
		nchars += bufsize;
		s = buffer;
		len = 0;

		ui_breakcheck();
		if (got_int)
		{
		    end = 0;		/* Interrupted, break loop */
		    break;
		}
	    }
#ifdef VMS
	    /*
	     * On VMS there is a problem: newlines get added when writing
	     * blocks at a time. Fix it by writing a line at a time.
	     * This is much slower!
	     * Explanation: VAX/DECC RTL insists that records in some RMS
	     * structures end with a newline (carriage return) character, and
	     * if they don't it adds one.
	     * With other RMS structures it works perfect without this fix.
	     */
	    if (buf->b_fab_rfm == FAB$C_VFC
		    || ((buf->b_fab_rat & (FAB$M_FTN | FAB$M_CR)) != 0))
	    {
		int b2write;

		buf->b_fab_mrs = (buf->b_fab_mrs == 0
			? MIN(4096, bufsize)
			: MIN(buf->b_fab_mrs, bufsize));

		b2write = len;
		while (b2write > 0)
		{
		    write_info.bw_len = MIN(b2write, buf->b_fab_mrs);
		    if (buf_write_bytes(&write_info) == FAIL)
		    {
			end = 0;
			break;
		    }
		    b2write -= MIN(b2write, buf->b_fab_mrs);
		}
		write_info.bw_len = bufsize;
		nchars += len;
		s = buffer;
		len = 0;
	    }
#endif
	}
	if (len > 0 && end > 0)
	{
	    write_info.bw_len = len;
	    if (buf_write_bytes(&write_info) == FAIL)
		end = 0;		    /* write error */
	    nchars += len;
	}

	/* Stop when writing done or an error was encountered. */
	if (!checking_conversion || end == 0)
	    break;

	/* If no error happened until now, writing should be ok, so loop to
	 * really write the buffer. */
    }

    /* If we started writing, finish writing. Also when an error was
     * encountered. */
    if (!checking_conversion)
    {
#if defined(UNIX) && defined(HAVE_FSYNC)
	/*
	 * On many journalling file systems there is a bug that causes both the
	 * original and the backup file to be lost when halting the system
	 * right after writing the file.  That's because only the meta-data is
	 * journalled.  Syncing the file slows down the system, but assures it
	 * has been written to disk and we don't lose it.
	 * For a device do try the fsync() but don't complain if it does not
	 * work (could be a pipe).
	 * If the 'fsync' option is FALSE, don't fsync().  Useful for laptops.
	 */
	if (p_fs && fsync(fd) != 0 && !device)
	{
	    errmsg = (char_u *)_("E667: Fsync failed");
	    end = 0;
	}
#endif

#if defined(HAVE_SELINUX) || defined(HAVE_SMACK)
	/* Probably need to set the security context. */
	if (!backup_copy)
	    mch_copy_sec(backup, wfname);
#endif

#ifdef UNIX
	/* When creating a new file, set its owner/group to that of the
	 * original file.  Get the new device and inode number. */
	if (backup != NULL && !backup_copy)
	{
# ifdef HAVE_FCHOWN
	    stat_T	st;

	    /* don't change the owner when it's already OK, some systems remove
	     * permission or ACL stuff */
	    if (mch_stat((char *)wfname, &st) < 0
		    || st.st_uid != st_old.st_uid
		    || st.st_gid != st_old.st_gid)
	    {
		ignored = fchown(fd, st_old.st_uid, st_old.st_gid);
		if (perm >= 0)	/* set permission again, may have changed */
		    (void)mch_setperm(wfname, perm);
	    }
# endif
	    buf_setino(buf);
	}
	else if (!buf->b_dev_valid)
	    /* Set the inode when creating a new file. */
	    buf_setino(buf);
#endif

	if (close(fd) != 0)
	{
	    errmsg = (char_u *)_("E512: Close failed");
	    end = 0;
	}

#ifdef UNIX
	if (made_writable)
	    perm &= ~0200;	/* reset 'w' bit for security reasons */
#endif
	if (perm >= 0)		/* set perm. of new file same as old file */
	    (void)mch_setperm(wfname, perm);
#ifdef HAVE_ACL
	/*
	 * Probably need to set the ACL before changing the user (can't set the
	 * ACL on a file the user doesn't own).
	 * On Solaris, with ZFS and the aclmode property set to "discard" (the
	 * default), chmod() discards all part of a file's ACL that don't
	 * represent the mode of the file.  It's non-trivial for us to discover
	 * whether we're in that situation, so we simply always re-set the ACL.
	 */
# ifndef HAVE_SOLARIS_ZFS_ACL
	if (!backup_copy)
# endif
	    mch_set_acl(wfname, acl);
#endif
#ifdef FEAT_CRYPT
	if (buf->b_cryptstate != NULL)
	{
	    crypt_free_state(buf->b_cryptstate);
	    buf->b_cryptstate = NULL;
	}
#endif

#if defined(FEAT_MBYTE) && defined(FEAT_EVAL)
	if (wfname != fname)
	{
	    /*
	     * The file was written to a temp file, now it needs to be
	     * converted with 'charconvert' to (overwrite) the output file.
	     */
	    if (end != 0)
	    {
		if (eval_charconvert(enc_utf8 ? (char_u *)"utf-8" : p_enc,
						  fenc, wfname, fname) == FAIL)
		{
		    write_info.bw_conv_error = TRUE;
		    end = 0;
		}
	    }
	    mch_remove(wfname);
	    vim_free(wfname);
	}
#endif
    }

    if (end == 0)
    {
	/*
	 * Error encountered.
	 */
	if (errmsg == NULL)
	{
#ifdef FEAT_MBYTE
	    if (write_info.bw_conv_error)
	    {
		if (write_info.bw_conv_error_lnum == 0)
		    errmsg = (char_u *)_("E513: write error, conversion failed (make 'fenc' empty to override)");
		else
		{
		    errmsg_allocated = TRUE;
		    errmsg = alloc(300);
		    vim_snprintf((char *)errmsg, 300, _("E513: write error, conversion failed in line %ld (make 'fenc' empty to override)"),
					 (long)write_info.bw_conv_error_lnum);
		}
	    }
	    else
#endif
		if (got_int)
		    errmsg = (char_u *)_(e_interr);
		else
		    errmsg = (char_u *)_("E514: write error (file system full?)");
	}

	/*
	 * If we have a backup file, try to put it in place of the new file,
	 * because the new file is probably corrupt.  This avoids losing the
	 * original file when trying to make a backup when writing the file a
	 * second time.
	 * When "backup_copy" is set we need to copy the backup over the new
	 * file.  Otherwise rename the backup file.
	 * If this is OK, don't give the extra warning message.
	 */
	if (backup != NULL)
	{
	    if (backup_copy)
	    {
		/* This may take a while, if we were interrupted let the user
		 * know we got the message. */
		if (got_int)
		{
		    MSG(_(e_interr));
		    out_flush();
		}
		if ((fd = mch_open((char *)backup, O_RDONLY | O_EXTRA, 0)) >= 0)
		{
		    if ((write_info.bw_fd = mch_open((char *)fname,
				    O_WRONLY | O_CREAT | O_TRUNC | O_EXTRA,
							   perm & 0777)) >= 0)
		    {
			/* copy the file. */
			write_info.bw_buf = smallbuf;
#ifdef HAS_BW_FLAGS
			write_info.bw_flags = FIO_NOCONVERT;
#endif
			while ((write_info.bw_len = read_eintr(fd, smallbuf,
						      SMBUFSIZE)) > 0)
			    if (buf_write_bytes(&write_info) == FAIL)
				break;

			if (close(write_info.bw_fd) >= 0
						   && write_info.bw_len == 0)
			    end = 1;		/* success */
		    }
		    close(fd);	/* ignore errors for closing read file */
		}
	    }
	    else
	    {
		if (vim_rename(backup, fname) == 0)
		    end = 1;
	    }
	}
	goto fail;
    }

    lnum -= start;	    /* compute number of written lines */
    --no_wait_return;	    /* may wait for return now */

#if !(defined(UNIX) || defined(VMS))
    fname = sfname;	    /* use shortname now, for the messages */
#endif
    if (!filtering)
    {
	msg_add_fname(buf, fname);	/* put fname in IObuff with quotes */
	c = FALSE;
#ifdef FEAT_MBYTE
	if (write_info.bw_conv_error)
	{
	    STRCAT(IObuff, _(" CONVERSION ERROR"));
	    c = TRUE;
	    if (write_info.bw_conv_error_lnum != 0)
		vim_snprintf_add((char *)IObuff, IOSIZE, _(" in line %ld;"),
			(long)write_info.bw_conv_error_lnum);
	}
	else if (notconverted)
	{
	    STRCAT(IObuff, _("[NOT converted]"));
	    c = TRUE;
	}
	else if (converted)
	{
	    STRCAT(IObuff, _("[converted]"));
	    c = TRUE;
	}
#endif
	if (device)
	{
	    STRCAT(IObuff, _("[Device]"));
	    c = TRUE;
	}
	else if (newfile)
	{
	    STRCAT(IObuff, shortmess(SHM_NEW) ? _("[New]") : _("[New File]"));
	    c = TRUE;
	}
	if (no_eol)
	{
	    msg_add_eol();
	    c = TRUE;
	}
	/* may add [unix/dos/mac] */
	if (msg_add_fileformat(fileformat))
	    c = TRUE;
#ifdef FEAT_CRYPT
	if (wb_flags & FIO_ENCRYPTED)
	{
	    crypt_append_msg(buf);
	    c = TRUE;
	}
#endif
	msg_add_lines(c, (long)lnum, nchars);	/* add line/char count */
	if (!shortmess(SHM_WRITE))
	{
	    if (append)
		STRCAT(IObuff, shortmess(SHM_WRI) ? _(" [a]") : _(" appended"));
	    else
		STRCAT(IObuff, shortmess(SHM_WRI) ? _(" [w]") : _(" written"));
	}

	set_keep_msg(msg_trunc_attr(IObuff, FALSE, 0), 0);
    }

    /* When written everything correctly: reset 'modified'.  Unless not
     * writing to the original file and '+' is not in 'cpoptions'. */
    if (reset_changed && whole && !append
#ifdef FEAT_MBYTE
	    && !write_info.bw_conv_error
#endif
	    && (overwriting || vim_strchr(p_cpo, CPO_PLUS) != NULL)
	    )
    {
	unchanged(buf, TRUE);
#ifdef FEAT_AUTOCMD
	/* b:changedtick is always incremented in unchanged() but that
	 * should not trigger a TextChanged event. */
	if (last_changedtick + 1 == CHANGEDTICK(buf)
					       && last_changedtick_buf == buf)
	    last_changedtick = CHANGEDTICK(buf);
#endif
	u_unchanged(buf);
	u_update_save_nr(buf);
    }

    /*
     * If written to the current file, update the timestamp of the swap file
     * and reset the BF_WRITE_MASK flags. Also sets buf->b_mtime.
     */
    if (overwriting)
    {
	ml_timestamp(buf);
	if (append)
	    buf->b_flags &= ~BF_NEW;
	else
	    buf->b_flags &= ~BF_WRITE_MASK;
    }

    /*
     * If we kept a backup until now, and we are in patch mode, then we make
     * the backup file our 'original' file.
     */
    if (*p_pm && dobackup)
    {
	char *org = (char *)buf_modname((buf->b_p_sn || buf->b_shortname),
							  fname, p_pm, FALSE);

	if (backup != NULL)
	{
	    stat_T	st;

	    /*
	     * If the original file does not exist yet
	     * the current backup file becomes the original file
	     */
	    if (org == NULL)
		EMSG(_("E205: Patchmode: can't save original file"));
	    else if (mch_stat(org, &st) < 0)
	    {
		vim_rename(backup, (char_u *)org);
		vim_free(backup);	    /* don't delete the file */
		backup = NULL;
#ifdef UNIX
		set_file_time((char_u *)org, st_old.st_atime, st_old.st_mtime);
#endif
	    }
	}
	/*
	 * If there is no backup file, remember that a (new) file was
	 * created.
	 */
	else
	{
	    int empty_fd;

	    if (org == NULL
		    || (empty_fd = mch_open(org,
				      O_CREAT | O_EXTRA | O_EXCL | O_NOFOLLOW,
					perm < 0 ? 0666 : (perm & 0777))) < 0)
	      EMSG(_("E206: patchmode: can't touch empty original file"));
	    else
	      close(empty_fd);
	}
	if (org != NULL)
	{
	    mch_setperm((char_u *)org, mch_getperm(fname) & 0777);
	    vim_free(org);
	}
    }

    /*
     * Remove the backup unless 'backup' option is set
     */
    if (!p_bk && backup != NULL && mch_remove(backup) != 0)
	EMSG(_("E207: Can't delete backup file"));

#ifdef FEAT_SUN_WORKSHOP
    if (usingSunWorkShop)
	workshop_file_saved((char *) ffname);
#endif

    goto nofail;

    /*
     * Finish up.  We get here either after failure or success.
     */
fail:
    --no_wait_return;		/* may wait for return now */
nofail:

    /* Done saving, we accept changed buffer warnings again */
    buf->b_saving = FALSE;

    vim_free(backup);
    if (buffer != smallbuf)
	vim_free(buffer);
#ifdef FEAT_MBYTE
    vim_free(fenc_tofree);
    vim_free(write_info.bw_conv_buf);
# ifdef USE_ICONV
    if (write_info.bw_iconv_fd != (iconv_t)-1)
    {
	iconv_close(write_info.bw_iconv_fd);
	write_info.bw_iconv_fd = (iconv_t)-1;
    }
# endif
#endif
#ifdef HAVE_ACL
    mch_free_acl(acl);
#endif

    if (errmsg != NULL)
    {
	int numlen = errnum != NULL ? (int)STRLEN(errnum) : 0;

	attr = HL_ATTR(HLF_E);	/* set highlight for error messages */
	msg_add_fname(buf,
#ifndef UNIX
		sfname
#else
		fname
#endif
		     );		/* put file name in IObuff with quotes */
	if (STRLEN(IObuff) + STRLEN(errmsg) + numlen >= IOSIZE)
	    IObuff[IOSIZE - STRLEN(errmsg) - numlen - 1] = NUL;
	/* If the error message has the form "is ...", put the error number in
	 * front of the file name. */
	if (errnum != NULL)
	{
	    STRMOVE(IObuff + numlen, IObuff);
	    mch_memmove(IObuff, errnum, (size_t)numlen);
	}
	STRCAT(IObuff, errmsg);
	emsg(IObuff);
	if (errmsg_allocated)
	    vim_free(errmsg);

	retval = FAIL;
	if (end == 0)
	{
	    MSG_PUTS_ATTR(_("\nWARNING: Original file may be lost or damaged\n"),
		    attr | MSG_HIST);
	    MSG_PUTS_ATTR(_("don't quit the editor until the file is successfully written!"),
		    attr | MSG_HIST);

	    /* Update the timestamp to avoid an "overwrite changed file"
	     * prompt when writing again. */
	    if (mch_stat((char *)fname, &st_old) >= 0)
	    {
		buf_store_time(buf, &st_old, fname);
		buf->b_mtime_read = buf->b_mtime;
	    }
	}
    }
    msg_scroll = msg_save;

#ifdef FEAT_PERSISTENT_UNDO
    /*
     * When writing the whole file and 'undofile' is set, also write the undo
     * file.
     */
    if (retval == OK && write_undo_file)
    {
	char_u	    hash[UNDO_HASH_SIZE];

	sha256_finish(&sha_ctx, hash);
	u_write_undo(NULL, FALSE, buf, hash);
    }
#endif

#ifdef FEAT_AUTOCMD
#ifdef FEAT_EVAL
    if (!should_abort(retval))
#else
    if (!got_int)
#endif
    {
	aco_save_T	aco;

	curbuf->b_no_eol_lnum = 0;  /* in case it was set by the previous read */

	/*
	 * Apply POST autocommands.
	 * Careful: The autocommands may call buf_write() recursively!
	 */
	aucmd_prepbuf(&aco, buf);

	if (append)
	    apply_autocmds_exarg(EVENT_FILEAPPENDPOST, fname, fname,
							  FALSE, curbuf, eap);
	else if (filtering)
	    apply_autocmds_exarg(EVENT_FILTERWRITEPOST, NULL, fname,
							  FALSE, curbuf, eap);
	else if (reset_changed && whole)
	    apply_autocmds_exarg(EVENT_BUFWRITEPOST, fname, fname,
							  FALSE, curbuf, eap);
	else
	    apply_autocmds_exarg(EVENT_FILEWRITEPOST, fname, fname,
							  FALSE, curbuf, eap);

	/* restore curwin/curbuf and a few other things */
	aucmd_restbuf(&aco);

#ifdef FEAT_EVAL
	if (aborting())	    /* autocmds may abort script processing */
	    retval = FALSE;
#endif
    }
#endif

    got_int |= prev_got_int;

    return retval;
}