Lib/atexit.py

   1 """
   2 atexit.py - allow programmer to define multiple exit functions to be executed
   3 upon normal program termination.
   4
   5 One public function, register, is defined.
   6 """
   7
   8 __all__ = ["register"]
   9
  10 _exithandlers = []
  11 def _run_exitfuncs():
  12     """run any registered exit functions
  13
  14     _exithandlers is traversed in reverse order so functions are executed
  15     last in, first out.
  16     """
  17
  18     while _exithandlers:
  19         func, targs, kargs = _exithandlers.pop()
  20         apply(func, targs, kargs)
  21
  22 def register(func, *targs, **kargs):
  23     """register a function to be executed upon normal program termination
  24
  25     func - function to be called at exit
  26     targs - optional arguments to pass to func
  27     kargs - optional keyword arguments to pass to func
  28     """
  29     _exithandlers.append((func, targs, kargs))
  30
  31 import sys
  32 try:
  33     x = sys.exitfunc
  34 except AttributeError:
  35     sys.exitfunc = _run_exitfuncs
  36 else:
  37     # if x isn't our own exit func executive, assume it's another
  38     # registered exit function - append it to our list...
  39     if x != _run_exitfuncs:
  40         register(x)
  41 del sys
  42
  43 if __name__ == "__main__":
  44     def x1():
  45         print "running x1"
  46     def x2(n):
  47         print "running x2(%s)" % `n`
  48     def x3(n, kwd=None):
  49         print "running x3(%s, kwd=%s)" % (`n`, `kwd`)
  50
  51     register(x1)
  52     register(x2, 12)
  53     register(x3, 5, "bar")
  54     register(x3, "no kwd args")