LXR busybox/miscutils/wall.c

   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 source tree.
   7 */
   8
   9//usage:#define wall_trivial_usage
  10//usage:        "[FILE]"
  11//usage:#define wall_full_usage "\n\n"
  12//usage:        "Write content of FILE or stdin to all logged-in users"
  13//usage:
  14//usage:#define wall_sample_usage
  15//usage:        "echo foo | wall\n"
  16//usage:        "wall ./mymessage"
  17
  18#include "libbb.h"
  19
  20int wall_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  21int wall_main(int argc UNUSED_PARAM, char **argv)
  22{
  23        struct utmp *ut;
  24        char *msg;
  25        int fd = argv[1] ? xopen(argv[1], O_RDONLY) : STDIN_FILENO;
  26
  27        msg = xmalloc_read(fd, NULL);
  28        if (ENABLE_FEATURE_CLEAN_UP && argv[1])
  29                close(fd);
  30        setutent();
  31        while ((ut = getutent()) != NULL) {
  32                char *line;
  33                if (ut->ut_type != USER_PROCESS)
  34                        continue;
  35                line = concat_path_file("/dev", ut->ut_line);
  36                xopen_xwrite_close(line, msg);
  37                free(line);
  38        }
  39        if (ENABLE_FEATURE_CLEAN_UP) {
  40                endutent();
  41                free(msg);
  42        }
  43        return EXIT_SUCCESS;
  44}
  45