append_command(char_u *cmd)
{
    size_t  len = STRLEN(IObuff);
    char_u  *s = cmd;
    char_u  *d;

    if (len > IOSIZE - 100)
    {
	// Not enough space, truncate and put in "...".
	d = IObuff + IOSIZE - 100;
	d -= mb_head_off(IObuff, d);
	STRCPY(d, "...");
    }
    STRCAT(IObuff, ": ");
    d = IObuff + STRLEN(IObuff);
    while (*s != NUL && d - IObuff + 5 < IOSIZE)
    {
	if (enc_utf8 ? (s[0] == 0xc2 && s[1] == 0xa0) : *s == 0xa0)
	{
	    s += enc_utf8 ? 2 : 1;
	    STRCPY(d, "<a0>");
	    d += 4;
	}
	else if (d - IObuff + (*mb_ptr2len)(s) + 1 >= IOSIZE)
	    break;
	else
	    MB_COPY_CHAR(s, d);
    }
    *d = NUL;
}
append_command(char_u *cmd)
{
    size_t  len = STRLEN(IObuff);
    char_u  *s = cmd;
    char_u  *d;

    if (len > IOSIZE - 100)
    {
	 
	d = IObuff + IOSIZE - 100;
	d -= mb_head_off(IObuff, d);
	STRCPY(d, "...");
    }
    STRCAT(IObuff, ": ");
    d = IObuff + STRLEN(IObuff);
    while (*s != NUL && d - IObuff + 5 < IOSIZE)
    {
	if (enc_utf8 ? (s[0] == 0xc2 && s[1] == 0xa0) : *s == 0xa0)
	{
	    s += enc_utf8 ? 2 : 1;
	    STRCPY(d, "<a0>");
	    d += 4;
	}
	else if (d - IObuff + (*mb_ptr2len)(s) + 1 >= IOSIZE)
	    break;
	else
	    MB_COPY_CHAR(s, d);
    }
    *d = NUL;
}