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
  34 #ifndef lint
  35 static const char copyright[] =
  36 "@(#) Copyright (c) 1988, 1993, 1994\n\
  37         The Regents of the University of California.  All rights reserved.\n";
  38 #endif /* not lint */
  39
  40 #if 0
  41 #ifndef lint
  42 static char sccsid[] = "@(#)env.c       8.3 (Berkeley) 4/2/94";
  43 #endif /* not lint */
  44 #endif
  45
  46 #include <sys/cdefs.h>
  47 __RCSID("$FreeBSD: src/usr.bin/env/env.c,v 1.11 2002/09/04 23:28:59 dwmalone Exp $");
  48
  49 #include <err.h>
  50 #include <errno.h>
  51 #include <stdio.h>
  52 #include <string.h>
  53 #include <stdlib.h>
  54 #include <unistd.h>
  55
  56 extern char **environ;
  57
  58 static void usage(void);
  59
  60 int
  61 main(int argc, char **argv)
  62 {
  63         char **ep, *p;
  64         char *cleanenv[1];
  65         int ch;
  66
  67         while ((ch = getopt(argc, argv, "-i")) != -1)
  68                 switch(ch) {
  69                 case '-':
  70                 case 'i':
  71                         environ = cleanenv;
  72                         cleanenv[0] = NULL;
  73                         break;
  74                 case '?':
  75                 default:
  76                         usage();
  77                 }
  78         for (argv += optind; *argv && (p = strchr(*argv, '=')); ++argv)
  79                 (void)setenv(*argv, ++p, 1);
  80         if (*argv) {
  81                 execvp(*argv, argv);
  82                 err(errno == ENOENT ? 127 : 126, "%s", *argv);
  83         }
  84         for (ep = environ; *ep; ep++)
  85                 (void)printf("%s\n", *ep);
  86         exit(0);
  87 }
  88
  89 static void
  90 usage(void)
  91 {
  92         (void)fprintf(stderr,
  93             "usage: env [-i] [name=value ...] [utility [argument ...]]\n");
  94         exit(1);
  95 }