getoldopt.c revision 1.4
1/* $NetBSD: getoldopt.c,v 1.4 1996/05/17 01:07:47 jtc Exp $ */ 2 3/* 4 * Plug-compatible replacement for getopt() for parsing tar-like 5 * arguments. If the first argument begins with "-", it uses getopt; 6 * otherwise, it uses the old rules used by tar, dump, and ps. 7 * 8 * Written 25 August 1985 by John Gilmore (ihnp4!hoptoad!gnu) and placed 9 * in the Public Domain for your edification and enjoyment. 10 */ 11 12#ifndef lint 13static char rcsid[] = "$NetBSD: getoldopt.c,v 1.4 1996/05/17 01:07:47 jtc Exp $"; 14#endif /* not lint */ 15 16#include <stdio.h> 17#include <string.h> 18#include <unistd.h> 19 20int 21getoldopt(argc, argv, optstring) 22 int argc; 23 char **argv; 24 char *optstring; 25{ 26 extern char *optarg; /* Points to next arg */ 27 extern int optind; /* Global argv index */ 28 static char *key; /* Points to next keyletter */ 29 static char use_getopt; /* !=0 if argv[1][0] was '-' */ 30 char c; 31 char *place; 32 33 optarg = NULL; 34 35 if (key == NULL) { /* First time */ 36 if (argc < 2) return EOF; 37 key = argv[1]; 38 if (*key == '-') 39 use_getopt++; 40 else 41 optind = 2; 42 } 43 44 if (use_getopt) 45 return getopt(argc, argv, optstring); 46 47 c = *key++; 48 if (c == '\0') { 49 key--; 50 return EOF; 51 } 52 place = strchr(optstring, c); 53 54 if (place == NULL || c == ':') { 55 fprintf(stderr, "%s: unknown option %c\n", argv[0], c); 56 return('?'); 57 } 58 59 place++; 60 if (*place == ':') { 61 if (optind < argc) { 62 optarg = argv[optind]; 63 optind++; 64 } else { 65 fprintf(stderr, "%s: %c argument missing\n", 66 argv[0], c); 67 return('?'); 68 } 69 } 70 71 return(c); 72} 73