1 /* $NetBSD: printenv.c,v 1.12 2011/09/06 18:26:55 joerg Exp $ */ 2 3 /* 4 * Copyright (c) 1987, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 #ifndef lint 34 __COPYRIGHT("@(#) Copyright (c) 1987, 1993\ 35 The Regents of the University of California. All rights reserved."); 36 #endif /* not lint */ 37 38 #ifndef lint 39 /*static char sccsid[] = "from: @(#)printenv.c 8.2 (Berkeley) 5/4/95";*/ 40 __RCSID("$NetBSD: printenv.c,v 1.12 2011/09/06 18:26:55 joerg Exp $"); 41 #endif /* not lint */ 42 43 #include <sys/types.h> 44 45 #include <stdlib.h> 46 #include <stdio.h> 47 #include <string.h> 48 #include <unistd.h> 49 #include <err.h> 50 51 __dead static void usage(void); 52 53 /* 54 * printenv 55 * 56 * Bill Joy, UCB 57 * February, 1979 58 */ 59 int 60 main(int argc, char *argv[]) 61 { 62 extern char **environ; 63 char *cp, **ep; 64 size_t len; 65 int ch; 66 67 while ((ch = getopt(argc, argv, "")) != -1) 68 switch(ch) { 69 case '?': 70 default: 71 usage(); 72 } 73 argc -= optind; 74 argv += optind; 75 76 if (argc == 0) { 77 for (ep = environ; *ep; ep++) 78 (void)printf("%s\n", *ep); 79 exit(0); 80 } 81 if (argc != 1) 82 usage(); 83 if (strchr(*argv, '=') != NULL) 84 errx(1, "Invalid environment variable %s", *argv); 85 len = strlen(*argv); 86 for (ep = environ; *ep; ep++) 87 if (!memcmp(*ep, *argv, len)) { 88 cp = *ep + len; 89 if (!*cp || *cp == '=') { 90 (void)printf("%s\n", *cp ? cp + 1 : cp); 91 exit(0); 92 } 93 } 94 exit(1); 95 } 96 97 static void 98 usage(void) 99 { 100 (void)fprintf(stderr, "Usage: printenv [name]\n"); 101 exit(1); 102 } 103
