closing file descriptors

[rory]

This piece of code bothers me in env.c:


  /*
   * Require that the other file descriptios are closed. Should we use
   * sysconf() or getdtablesize() or getrlimit() or...
   */
  for(i = 3; i < 1024; i++)
      (void) close(i);
  errno= 0;


I don't understand why this is done.