getoldopt.c revision 1.1 
1/*
2 * Plug-compatible replacement for getopt() for parsing tar-like
3 * arguments.  If the first argument begins with "-", it uses getopt;
4 * otherwise, it uses the old rules used by tar, dump, and ps.
5 *
6 * Written 25 August 1985 by John Gilmore (ihnp4!hoptoad!gnu) and placed
7 * in the Pubic Domain for your edification and enjoyment.
8 */
9
10#ifndef lint
11static char *rcsid = "$Id: getoldopt.c,v 1.1 1994/06/14 01:16:07 jtc Exp $";
12#endif /* not lint */
13
14#include <stdio.h>
15#include <string.h>
16
17int
18getoldopt(argc, argv, optstring)
19	int	argc;
20	char	**argv;
21	char	*optstring;
22{
23	extern char	*optarg;	/* Points to next arg */
24	extern int	optind;		/* Global argv index */
25	static char	*key;		/* Points to next keyletter */
26	static char	use_getopt;	/* !=0 if argv[1][0] was '-' */
27	char		c;
28	char		*place;
29
30	optarg = NULL;
31
32	if (key == NULL) {		/* First time */
33		if (argc < 2) return EOF;
34		key = argv[1];
35		if (*key == '-')
36			use_getopt++;
37		else
38			optind = 2;
39	}
40
41	if (use_getopt)
42		return getopt(argc, argv, optstring);
43
44	c = *key++;
45	if (c == '\0') {
46		key--;
47		return EOF;
48	}
49	place = strchr(optstring, c);
50
51	if (place == NULL || c == ':') {
52		fprintf(stderr, "%s: unknown option %c\n", argv[0], c);
53		return('?');
54	}
55
56	place++;
57	if (*place == ':') {
58		if (optind < argc) {
59			optarg = argv[optind];
60			optind++;
61		} else {
62			fprintf(stderr, "%s: %c argument missing\n",
63				argv[0], c);
64			return('?');
65		}
66	}
67
68	return(c);
69}
70