libexpat - Fix buildworld
[dragonfly.git] / contrib / tcp_wrappers / setenv.c
blob03c706280c6412e5bb693bddf0934d04c86e4e52
1 /*
2 * Some systems do not have setenv(). This one is modeled after 4.4 BSD, but
3 * is implemented in terms of portable primitives only: getenv(), putenv()
4 * and malloc(). It should therefore be safe to use on every UNIX system.
5 *
6 * If clobber == 0, do not overwrite an existing variable.
7 *
8 * Returns nonzero if memory allocation fails.
9 *
10 * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
13 #ifndef lint
14 static char sccsid[] = "@(#) setenv.c 1.1 93/03/07 22:47:58";
15 #endif
17 /* setenv - update or insert environment (name,value) pair */
19 int setenv(name, value, clobber)
20 char *name;
21 char *value;
22 int clobber;
24 char *malloc();
25 char *getenv();
26 char *cp;
28 if (clobber == 0 && getenv(name) != 0)
29 return (0);
30 if ((cp = malloc(strlen(name) + strlen(value) + 2)) == 0)
31 return (1);
32 sprintf(cp, "%s=%s", name, value);
33 return (putenv(cp));