usr.bin/env/env.c

   1 /*
   2  * Copyright (c) 1988, 1993, 1994
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  * @(#) Copyright (c) 1988, 1993, 1994 The Regents of the University of California.  All rights reserved.
  34  * @(#)env.c    8.3 (Berkeley) 4/2/94
  35  * $FreeBSD: src/usr.bin/env/env.c,v 1.5.2.3 2002/06/26 08:23:36 tjr Exp $
  36  * $DragonFly: src/usr.bin/env/env.c,v 1.5 2006/01/12 13:43:10 corecode Exp $
  37  */
  38
  39 #include <err.h>
  40 #include <errno.h>
  41 #include <stdio.h>
  42 #include <string.h>
  43 #include <stdlib.h>
  44 #include <unistd.h>
  45
  46 extern char **environ;
  47
  48 static void usage(void);
  49
  50 int
  51 main(int argc, char **argv)
  52 {
  53         char **ep, *p;
  54         char *cleanenv[1];
  55         int ch;
  56
  57         while ((ch = getopt(argc, argv, "-i")) != -1)
  58                 switch(ch) {
  59                 case '-':
  60                 case 'i':
  61                         environ = cleanenv;
  62                         cleanenv[0] = NULL;
  63                         break;
  64                 default:
  65                         usage();
  66                 }
  67         for (argv += optind; *argv && (p = strchr(*argv, '=')); ++argv) {
  68                 if (setenv(*argv, ++p, 1) == -1)
  69                         err(1, "setenv: cannot set %s=%s", *argv, p);
  70         }
  71
  72         if (*argv) {
  73                 execvp(*argv, argv);
  74                 err(errno == ENOENT ? 127 : 126, "%s", *argv);
  75         }
  76         for (ep = environ; *ep; ep++)
  77                 printf("%s\n", *ep);
  78         exit(0);
  79 }
  80
  81 static void
  82 usage(void)
  83 {
  84         fprintf(stderr,
  85             "usage: env [-i] [name=value ...] [utility [argument ...]]\n");
  86         exit(1);
  87 }