getopt.c

<B>Digital的Unix操作系统VAX 4.2源码</B>

#ifndef lint
static char sccsid[] = "@(#)getopt.c	4.1 (decvax!larry) 7/2/90";
#endif

/************
 *  get options from argument list
 **********/

/* 
 * decvax!larry - no change since BSD 4.2
 */

#include	<stdio.h>
#define ERR(s, c)	if(opterr){\
	fputs(argv[0], stderr);\
	fputs(s, stderr);\
	fputc(c, stderr);\
	fputc('\n', stderr);} else

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

extern char *index();

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

	if (sp == 1)
		if (optind >= argc ||
		   argv[optind][0] != '-' || argv[optind][1] == '\0')
			return EOF;
		else if (strcmp(argv[optind], "--") == NULL) {
			optind++;
			return EOF;
		}
	optopt = c = argv[optind][sp];
	if (c == ':' || (cp=index(opts, c)) == NULL) {
		ERR (": illegal option -- ", c);
		if (argv[optind][++sp] == '\0') {
			optind++;
			sp = 1;
		}
		return '?';
	}
	if (*++cp == ':') {
		if (argv[optind][sp+1] != '\0')
			optarg = &argv[optind++][sp+1];
		else if (++optind >= argc) {
			ERR (": option requires an argument -- ", c);
			sp = 1;
			return '?';
		} else
			optarg = argv[optind++];
		sp = 1;
	}
	else {
		if (argv[optind][++sp] == '\0') {
			sp = 1;
			optind++;
		}
		optarg = NULL;
	}
	return c;
}