1 /* 2 * Copyright (c) 1987, 1993 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. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#) Copyright (c) 1987, 1993 The Regents of the University of California. All rights reserved. 30 * @(#)printenv.c 8.2 (Berkeley) 5/4/95 31 * 32 * $DragonFly: src/usr.bin/printenv/printenv.c,v 1.4 2005/01/07 02:32:50 cpressey Exp $ 33 */ 34 35 #include <sys/types.h> 36 37 #include <stdlib.h> 38 #include <stdio.h> 39 #include <string.h> 40 #include <unistd.h> 41 42 extern char **environ; 43 44 static void usage(void); 45 46 /* 47 * printenv 48 * 49 * Bill Joy, UCB 50 * February, 1979 51 */ 52 int 53 main(int argc, char **argv) 54 { 55 char *cp, **ep; 56 size_t len; 57 int ch; 58 59 while ((ch = getopt(argc, argv, "")) != -1) { 60 switch(ch) { 61 case '?': 62 default: 63 usage(); 64 } 65 } 66 argc -= optind; 67 argv += optind; 68 69 if (argc == 0) { 70 for (ep = environ; *ep != NULL; ep++) 71 printf("%s\n", *ep); 72 exit(0); 73 } 74 len = strlen(*argv); 75 for (ep = environ; *ep != NULL; ep++) { 76 cp = strchr(*ep, '='); 77 if (cp == *ep + len) { 78 if (memcmp(*ep, *argv, len) == 0) { 79 printf("%s\n", cp + 1); 80 exit(0); 81 } 82 } 83 } 84 exit(1); 85 } 86 87 static void 88 usage(void) 89 { 90 fprintf(stderr, "usage: printenv [name]\n"); 91 exit(1); 92 } 93