/* * mesg -- set current tty to accept or forbid writes * * mesg [y] [n] * y allow messages * n forbid messages */ int sbuf[40]; main(argc, argv) char *argv[]; { register char *tty; tty = "/dev/ttyx"; tty[8] = ttyn(1); if(stat(tty, sbuf) == -1) { perror(tty); return 1; } if(argc < 2) { if(sbuf[2] & 02) goto no; else goto yes; } if(*argv[1] == 'y') goto yes; no: if(chmod(tty, 0600) == -1) goto bad; goto was; yes: if(chmod(tty, 0602) == -1) goto bad; was: if(sbuf[2] & 02) write(2, "was y\n", 6); else write(2, "was n\n", 6); return 0; bad: perror("cannot change"); return 1; }