diff --git a/sbin/init/init.c b/sbin/init/init.c
index c06aff539f3..54d59f6d825 100644
--- a/sbin/init/init.c
+++ b/sbin/init/init.c
@@ -974,7 +974,7 @@ single_user(void)
 		char name[] = "-sh";
 
 		argv[0] = name;
-		argv[1] = 0;
+		argv[1] = NULL;
 		execv(shell, argv);
 		emergency("can't exec %s for single user: %m", shell);
 		execv(_PATH_BSHELL, argv);
@@ -1134,7 +1134,7 @@ run_script(const char *script)
 		argv[0] = _sh;
 		argv[1] = __DECONST(char *, script);
 		argv[2] = runcom_mode == AUTOBOOT ? _autoboot : 0;
-		argv[3] = 0;
+		argv[3] = NULL;
 
 		execute_script(argv);
 		sleep(STALL_TIMEOUT);
@@ -1478,10 +1478,10 @@ start_window_system(session_t *sp)
 		strcpy(term, "TERM=");
 		strlcat(term, sp->se_type, sizeof(term));
 		env[0] = term;
-		env[1] = 0;
+		env[1] = NULL;
 	}
 	else
-		env[0] = 0;
+		env[0] = NULL;
 	execve(sp->se_window_argv[0], sp->se_window_argv, env);
 	stall("can't exec window system '%s' for port %s: %m",
 		sp->se_window_argv[0], sp->se_device);
@@ -1542,9 +1542,9 @@ start_getty(session_t *sp)
 		strcpy(term, "TERM=");
 		strlcat(term, sp->se_type, sizeof(term));
 		env[0] = term;
-		env[1] = 0;
+		env[1] = NULL;
 	} else
-		env[0] = 0;
+		env[0] = NULL;
 	execve(sp->se_getty_argv[0], sp->se_getty_argv, env);
 	stall("can't exec getty '%s' for port %s: %m",
 		sp->se_getty_argv[0], sp->se_device);
@@ -1928,7 +1928,7 @@ runshutdown(void)
 		argv[0] = _sh;
 		argv[1] = _path_rundown;
 		argv[2] = Reboot ? _reboot : _single;
-		argv[3] = 0;
+		argv[3] = NULL;
 		
 		execute_script(argv);
 		_exit(1);	/* force single user mode */