2.9BSD - /usr/src/cmd/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: #include <stdio.h>
  11: #include <sys/types.h>
  12: #include <sys/stat.h>
  13: 
  14: struct stat sbuf;
  15: 
  16: char *tty;
  17: char *ttyname();
  18: 
  19: main(argc, argv)
  20: char *argv[];
  21: {
  22:     int r=0;
  23:     tty = ttyname(2);
  24:     if(stat(tty, &sbuf) < 0) error("cannot stat");
  25:     if(argc < 2) {
  26:         if(sbuf.st_mode & 02)
  27:             fprintf(stderr,"is y\n");
  28:         else {  r=1;
  29:             fprintf(stderr,"is n\n");
  30:         }
  31:     } else  switch(*argv[1]) {
  32:         case 'y':
  33:             newmode(0622); break;
  34: 
  35:         case 'n':
  36:             newmode(0600); r=1; break;
  37: 
  38:         default:
  39:             error("usage: mesg [y] [n]");
  40:         }
  41:     exit(r);
  42: }
  43: 
  44: error(s)
  45: char *s;
  46: {
  47:     fprintf(stderr,"mesg: %s\n",s);
  48:     exit(-1);
  49: }
  50: 
  51: newmode(m)
  52: {
  53:     if(chmod(tty,m)<0)
  54:         error("cannot change mode");
  55: }

Defined functions

Defined variables