1/* vi: set sw=4 ts=4: */
2/*
3 * wall - write a message to all logged-in users
4 * Copyright (c) 2009 Bernhard Reutner-Fischer
5 *
6 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
7 */
8
9#include "libbb.h"
10#include <utmp.h>
11
12int wall_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
13int wall_main(int argc UNUSED_PARAM, char **argv)
14{
15	struct utmp *ut;
16	char *msg;
17	int fd = argv[1] ? xopen(argv[1], O_RDONLY) : STDIN_FILENO;
18
19	msg = xmalloc_read(fd, NULL);
20	if (ENABLE_FEATURE_CLEAN_UP && argv[1])
21		close(fd);
22	setutent();
23	while ((ut = getutent()) != NULL) {
24		char *line;
25		if (ut->ut_type != USER_PROCESS)
26			continue;
27		line = concat_path_file("/dev", ut->ut_line);
28		xopen_xwrite_close(line, msg);
29		free(line);
30	}
31	if (ENABLE_FEATURE_CLEAN_UP) {
32		endutent();
33		free(msg);
34	}
35	return EXIT_SUCCESS;
36}
37