1 /* vi: set sw=4 ts=4: */
3 * wall - write a message to all logged-in users
4 * Copyright (c) 2009 Bernhard Reutner-Fischer
6 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
12 //config: depends on FEATURE_UTMP
14 //config: Write a message to all users that are logged in.
16 /* Needs to be run by root or be suid root - needs to write to /dev/TTY: */
17 //applet:IF_WALL(APPLET(wall, BB_DIR_USR_BIN, BB_SUID_REQUIRE))
19 //kbuild:lib-$(CONFIG_WALL) += wall.o
21 //usage:#define wall_trivial_usage
23 //usage:#define wall_full_usage "\n\n"
24 //usage: "Write content of FILE or stdin to all logged-in users"
26 //usage:#define wall_sample_usage
27 //usage: "echo foo | wall\n"
28 //usage: "wall ./mymessage"
32 int wall_main(int argc
, char **argv
) MAIN_EXTERNALLY_VISIBLE
;
33 int wall_main(int argc UNUSED_PARAM
, char **argv
)
41 /* The applet is setuid.
42 * Access to the file must be under user's uid/gid.
44 fd
= xopen_as_uid_gid(argv
[1], O_RDONLY
, getuid(), getgid());
46 msg
= xmalloc_read(fd
, NULL
);
47 if (ENABLE_FEATURE_CLEAN_UP
&& argv
[1])
50 while ((ut
= getutent()) != NULL
) {
52 if (ut
->ut_type
!= USER_PROCESS
)
54 line
= concat_path_file("/dev", ut
->ut_line
);
55 xopen_xwrite_close(line
, msg
);
58 if (ENABLE_FEATURE_CLEAN_UP
) {