#### 3.4.3 Misc support routines

These are called by `newlib` but don’t apply to the embedded environment. `isatty()` is self explanatory. `kill()` doesn’t apply either in an environment withno process control, so it justs exits, which is a similar enough behavior. `getpid()` can safely return any value greater than 1. The value doesn’t effect anything in `newlib` because once again there is no process control.

    /*
     * isatty -- returns 1 if connected to a terminal device,
     *           returns 0 if not. Since we're hooked up to a
     *           serial port, we'll say yes and return a 1.
     */
    int
    isatty(fd)
         int fd;
    {
      return (1);
    }

    /*
     * getpid -- only one process, so just return 1.
     */
    #define __MYPID 1
    int
    getpid()
    {
      return __MYPID;
    }

    /*
     * kill -- go out via exit...
     */
    int
    kill(pid, sig)
         int pid;
         int sig;
    {
      if(pid == __MYPID)
        _exit(sig);
      return 0;
    }