text: /*
   * Copyright (c) 1990 Regents of the University of California.
   * All rights reserved.
   *
   * %sccs.include.redist.c%
   */
  
  /*
  FUNCTION
  <<atexit>>---request execution of functions at program exit
  
  INDEX
  	atexit
  
  SYNOPSIS
  	#include <stdlib.h>
  	int atexit (void (*<[function]>)(void));
  
  DESCRIPTION
  You can use <<atexit>> to enroll functions in a list of functions that
  will be called when your program terminates normally.  The argument is
  a pointer to a user-defined function (which must not require arguments and
  must not return a result).
  
  The functions are kept in a LIFO stack; that is, the last function
  enrolled by <<atexit>> will be the first to execute when your program
  exits.
  
  There is no built-in limit to the number of functions you can enroll
  in this list; however, after every group of 32 functions is enrolled,
  <<atexit>> will call <<malloc>> to get space for the next part of the
  list.   The initial list of 32 functions is statically allocated, so
  you can always count on at least that many slots available.
  
  RETURNS
  <<atexit>> returns <<0>> if it succeeds in enrolling your function,
  <<-1>> if it fails (possible only if no space was available for
  <<malloc>> to extend the list of functions).
  
  PORTABILITY
  <<atexit>> is required by the ANSI standard, which also specifies that
  implementations must support enrolling at least 32 functions.
  
  Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
  <<lseek>>, <<read>>, <<sbrk>>, <<write>>.
  */
  
  #include <stdlib.h>
  #include "atexit.h"
  
  /*
   * Register a function to be performed at exit.
   */
  
  int
  _DEFUN (atexit,
  	(fn),
  	_VOID _EXFNPTR(fn, (_VOID)))
  {
    return __register_exitproc (__et_atexit, fn, NULL, NULL);
  }
  