UNIX 6th Ed. - /usr/source/s2/mesg.c

   1: /*
   2:  * mesg -- set current tty to accept or
   3:  *	forbid write permission.
   4:  *
   5:  *	mesg [y] [n]
   6:  *		y allow messages
   7:  *		n forbid messages
   8:  */
   9: 
  10: int sbuf[40];
  11: 
  12: main(argc, argv)
  13: char *argv[];
  14: {
  15:     register char *tty;
  16: 
  17:     tty = "/dev/ttyx";
  18:     tty[8] = ttyn(1);
  19:     if(stat(tty, sbuf) < 0) {
  20:         write(2, "cannot stat\n", 12);
  21:         exit(1);
  22:     }
  23:     if(argc < 2) {
  24:         if(sbuf[2] & 02)
  25:             goto no;
  26:         goto yes;
  27:     }
  28:     if(*argv[1] == 'y')
  29:         goto yes;
  30: 
  31: no:
  32:     if(chmod(tty, 0600) < 0)
  33:         goto bad;
  34:     goto was;
  35: 
  36: yes:
  37:     if(chmod(tty, 0622) < 0)
  38:         goto bad;
  39: 
  40: was:
  41:     if(sbuf[2] & 02)
  42:         write(2, "was y\n", 6); else
  43:         write(2, "was n\n", 6);
  44:     exit(0);
  45: 
  46: bad:
  47:     write(2, "cannot change mode\n", 19);
  48:     exit(1);
  49: }

Defined functions

Defined variables