PR_ASSERT(0 == *internal->xargv);
if (0 != *internal->xargv) return PL_OPT_BAD;
PR_IMPLEMENT(PLOptStatus) PL_GetNextOpt(PLOptState *opt){    PLOptionInternal *internal = opt->internal;    PRIntn cop, eoo = PL_strlen(internal->options);    /*    ** If the current xarg points to nul, advance to the next    ** element of the argv vector. If the vector index is equal    ** to argc, we're out of arguments, so return an EOL.	** Note whether the first character of the new argument is	** a '-' and skip by it if it is.    */    while (0 == *internal->xargv)    {        internal->xargc += 1;        if (internal->xargc >= internal->argc)		{			opt->option = 0;			opt->value = NULL;			return PL_OPT_EOL;		}        internal->xargv = internal->argv[internal->xargc];		internal->minus = ('-' == *internal->xargv ? PR_TRUE : PR_FALSE);  /* not it */		if (internal->minus) internal->xargv += 1;  /* and consume */    }    /*    ** If we already have a '-' in hand, xargv points to the next    ** option. See if we can find a match in the list of possible    ** options supplied.    */    if (internal->minus)    {        for (cop = 0; cop < eoo; ++cop)        {            if (internal->options[cop] == *internal->xargv)            {                opt->option = *internal->xargv;                internal->xargv += 1;                /*                ** if options indicates that there's an associated				** value, this argv is finished and the next is the				** option's value.                */                if (':' == internal->options[cop + 1])                {					PR_ASSERT(0 == *internal->xargv);                    opt->value = internal->argv[++(internal->xargc)];                    internal->xargv = &static_Nul;                    internal->minus = PR_FALSE;                }				else opt->value = NULL;                return PL_OPT_OK;            }        }        internal->xargv += 1;  /* consume that option */        return PL_OPT_BAD;    }    /*    ** No '-', so it must be a standalone value. The option is nul.    */    opt->value = internal->argv[(internal->xargc)++];    internal->xargv = &static_Nul;    opt->option = 0;    return PL_OPT_OK;}  /* PL_GetNextOpt */