examples/Stdlib/ConsoleApp/GETOPT.C

// Copyright (c) 1997-2009 Nokia Corporation and/or its subsidiary(-ies).
// All rights reserved.
// This component and the accompanying materials are made available
// under the terms of "Eclipse Public License v1.0"
// which accompanies this distribution, and is available
// at the URL "http://www.eclipse.org/legal/epl-v10.html".
//
// Initial Contributors:
// Nokia Corporation - initial contribution.
//
// Contributors:
//
// Description:
//

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)getopt.c    8.2 (Berkeley) 4/2/94";
#endif /* LIBC_SCCS and not lint */

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

int     opterr = 1,             /* if error message should be printed */
        optind = 1,             /* index into parent argv vector */
        optopt,                 /* character checked for validity */
        optreset;               /* reset getopt */
char    *optarg;                /* argument associated with option */

#define BADCH   (int)'?'
#define BADARG  (int)':'
#define EMSG    ""

/*
 * getopt --
 *      Parse argc/argv argument vector.
 */
int
getopt(int nargc, char * const *nargv, const char *ostr)
{
//      extern char *__progname;
        static char *place = EMSG;              /* option letter processing */
        char *oli=NULL;                         /* option letter list index */

        if (optreset || !*place) {              /* update scanning pointer */
                optreset = 0;
                if (optind >= nargc || *(place = nargv[optind]) != '-') {
                        place = EMSG;
                        return (EOF);
                }
                if (place[1] && *++place == '-') {      /* found "--" */
                        ++optind;
                        place = EMSG;
                        return (EOF);
                }
        }                                       /* option letter okay? */

        optopt = (int)*place++;
        if (optopt != (int)':') oli = strchr(ostr, optopt);
        if ((optopt == (int)':') || !oli)
                {
                /*
                 * if the user didn't specify '-' as an option,
                 * assume it means EOF.
                 */
                if (optopt == (int)'-')
                        return (EOF);
                if (!*place)
                        ++optind;
                if (opterr && *ostr != ':')
                        (void)fprintf(stderr,
//                          "%s: illegal option -- %c\n", __progname, optopt);
                                "illegal option -- %c\n", optopt);
                return (BADCH);
                }
        if (*++oli != ':') {                    /* don't need argument */
                optarg = NULL;
                if (!*place)
                        ++optind;
        }
        else {                                  /* need an argument */
                if (*place)                     /* no white space */
                        optarg = place;
                else if (nargc <= ++optind) {   /* no arg */
                        place = EMSG;
                        if (*ostr == ':')
                                return (BADARG);
                        if (opterr)
                                (void)fprintf(stderr,
//                                  "%s: option requires an argument -- %c\n",
//                                  __progname, optopt);
                                    "option requires an argument -- %c\n",
                                        optopt);
                        return (BADCH);
                }
                else                            /* white space */
                        optarg = nargv[optind];
                place = EMSG;
                ++optind;
        }
        return (optopt);                        /* dump back option letter */
}

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