Colony » Colony Scout

/*-

 * Copyright (c) 2009, Kohsuke Ohtani

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 * 3. Neither the name of the author nor the names of any co-contributors

 *    may be used to endorse or promote products derived from this software

 *    without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND

 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE

 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 */

/*

 * environ.c - test POSIX environment variable

 */

#include <stdio.h>

#include <stdlib.h>

#include <unistd.h>

extern char **environ;

static void

oops(void)

{

        printf("oops!\n");

        exit(1);

}

static void

show_env(void)

{

        char **envp = environ;

        int i;

        for (i = 0; envp[i] != NULL; i++) {

                printf("envp[%d]: %s\n", i, envp[i]);

        }

}

int

main(int argc, char *argv[])

{

        char *val;

        printf("test environment variables\n");

        /* Show environment passed by shell */

        printf("show env\n");

        show_env();

        /* Set new viriable */

        printf("setenv-1\n");

        setenv("PATH", "/boot", 1);

        show_env();

        /* Overwirte existing viriable */

        printf("setenv-2\n");

        setenv("PATH", "/boot:/bin", 1);

        show_env();

        /* No overwirte please... */

        printf("setenv-3\n");

        setenv("PATH", "/boot", 0);

        show_env();

        /* No overwirte please... */

        printf("setenv-4\n");

        setenv("PATH", "/boot", 0);

        show_env();

        /* Get non existing variable */

        printf("getenv-1\n");

        val = getenv("TMP");

        if (val != NULL)

                oops();

        /* Get existing variable */

        printf("getenv-2\n");

        val = getenv("PATH");

        if (val == NULL)

                oops();

        printf("PATH=%s\n", val);

        /* putenv */

        printf("putenv-1\n");

        putenv("TMP=/tmp");

        show_env();

        printf("putenv-2\n");

        putenv("ABC=/abc");

        show_env();

        exit(0);

}