1 /* 2 * Copyright (c) 1987, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 */ 7 8 #ifndef lint 9 static char copyright[] = 10 "@(#) Copyright (c) 1987, 1993\n\ 11 The Regents of the University of California. All rights reserved.\n"; 12 #endif /* not lint */ 13 14 #ifndef lint 15 static char sccsid[] = "@(#)printenv.c 8.1 (Berkeley) 06/06/93"; 16 #endif /* not lint */ 17 18 #include <sys/types.h> 19 20 #include <stdlib.h> 21 #include <stdio.h> 22 #include <string.h> 23 24 void usage __P((void)); 25 26 /* 27 * printenv 28 * 29 * Bill Joy, UCB 30 * February, 1979 31 */ 32 int 33 main(argc, argv) 34 int argc; 35 char *argv[]; 36 { 37 extern char **environ; 38 register char *cp, **ep; 39 register size_t len; 40 int ch; 41 42 while ((ch = getopt(argc, argv, "")) != EOF) 43 switch(ch) { 44 case '?': 45 default: 46 usage(); 47 } 48 argc -= optind; 49 argv += optind; 50 51 if (argc == 0) { 52 for (ep = environ; *ep; ep++) 53 (void)printf("%s\n", *ep); 54 exit(0); 55 } 56 len = strlen(*argv); 57 for (ep = environ; *ep; ep++) 58 if (!memcmp(*ep, *argv, len)) { 59 cp = *ep + len; 60 if (!*cp || *cp == '=') { 61 (void)printf("%s\n", *cp ? cp + 1 : cp); 62 exit(0); 63 } 64 } 65 exit(1); 66 } 67 68 void 69 usage() 70 { 71 (void)fprintf(stderr, "usage: printenv [name]\n"); 72 exit(1); 73 } 74