#include <stdio.h>
#include <string.h>

int optind = 1;
int optopt;
char *optarg;

int getopt(int argc, char **argv, const char *opts)
{
    static int sp = 1;
    register int c;
    register const char *cp;

    if (sp == 1) {
						
	/* If all args are processed, finish */
	if (optind >= argc) {
	    return EOF;
	}
	if (argv[optind][0] != '-' || argv[optind][1] == '\0') {
	    return EOF;
	}
    } else if (!strcmp(argv[optind], "--")) {
																											
	/* No more options to be processed after this one */
	optind++;
	return EOF;
    }

    optopt = c = argv[optind][sp];

    /* Check for invalid option */
    if (c == ':' || (cp = strchr(opts, c)) == NULL) {
	fprintf(stderr,
		"%s: illegal option -- %c\n",
		argv[0],
		c);
	if (argv[optind][++sp] == '\0') {
	    optind++;
	    sp = 1;
	}
	return '?';
    }

    /* Does this option require an argument? */
    if (*++cp == ':') {

	/* If so, get argument; if none provided output error */
	if (argv[optind][sp+1] != '\0') {
	    optarg = &argv[optind++][sp+1];
	} else if (++optind >= argc) {
	    fprintf(stderr,
		    "%s: option requires an argument -- %c\n",
		    argv[0],
		    c);
	    sp = 1;
	    return '?';
	} else {
	    optarg = argv[optind++];
	}
	sp = 1;

    } else {
	if (argv[optind][++sp] == '\0') {
	    sp = 1;
	    optind++;
	}
	optarg = NULL;
    }
																																																																																																																												
    return c;
}