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[unix-history] / usr / src / usr.bin / diction / getopt.c

#ifndef lint
static char sccsid[] = "@(#)getopt.c    4.2     (Berkeley)      82/11/06";
#endif not lint

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

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