xref: /original-bsd/usr.bin/printenv/printenv.c (revision e59fb703)
1 /*
2  * Copyright (c) 1987 Regents of the University of California.
3  * All rights reserved.
4  *
5  * %sccs.include.redist.c%
6  */
7 
8 #ifndef lint
9 char copyright[] =
10 "@(#) Copyright (c) 1987 Regents of the University of California.\n\
11  All rights reserved.\n";
12 #endif /* not lint */
13 
14 #ifndef lint
15 static char sccsid[] = "@(#)printenv.c	5.4 (Berkeley) 06/01/90";
16 #endif /* not lint */
17 
18 /*
19  * printenv
20  *
21  * Bill Joy, UCB
22  * February, 1979
23  */
24 main(argc, argv)
25 	int argc;
26 	char **argv;
27 {
28 	extern char **environ;
29 	register char *cp, **ep;
30 	register int len;
31 
32 	if (argc < 2) {
33 		for (ep = environ; *ep; ep++)
34 			puts(*ep);
35 		exit(0);
36 	}
37 	len = strlen(*++argv);
38 	for (ep = environ; *ep; ep++)
39 		if (!strncmp(*ep, *argv, len)) {
40 			cp = *ep + len;
41 			if (!*cp || *cp == '=') {
42 				puts(*cp ? cp + 1 : cp);
43 				exit(0);
44 			}
45 		}
46 	exit(1);
47 }
48