Patch #1680961: remove sys.exitfunc and replace it with a private C API. Also, reimplement atexit in C so it can take advantage of this private API.

2 files changed, 17 insertions, 32 deletions

diff --git a/Doc/lib/libatexit.tex b/Doc/lib/libatexit.tex
index 9798b57..04f1d49 100644
--- a/Doc/lib/libatexit.tex
+++ b/Doc/lib/libatexit.tex
@@ -1,32 +1,21 @@
 \section{\module{atexit} ---
          Exit handlers}
 
-\declaremodule{standard}{atexit}
+\declaremodule{builtin}{atexit}
 \moduleauthor{Skip Montanaro}{skip@mojam.com}
 \sectionauthor{Skip Montanaro}{skip@mojam.com}
 \modulesynopsis{Register and execute cleanup functions.}
 
 \versionadded{2.0}
 
-The \module{atexit} module defines a single function to register
-cleanup functions.  Functions thus registered are automatically
-executed upon normal interpreter termination.
 
-Note: the functions registered via this module are not called when the program is killed by a
-signal, when a Python fatal internal error is detected, or when
-\function{os._exit()} is called.
+The \module{atexit} module defines functions to register and
+unregister cleanup functions.  Functions thus registered are
+automatically executed upon normal interpreter termination.
 
-This is an alternate interface to the functionality provided by the
-\code{sys.exitfunc} variable.
-\withsubitem{(in sys)}{\ttindex{exitfunc}}
-
-Note: This module is unlikely to work correctly when used with other code
-that sets \code{sys.exitfunc}.  In particular, other core Python modules are
-free to use \module{atexit} without the programmer's knowledge.  Authors who
-use \code{sys.exitfunc} should convert their code to use
-\module{atexit} instead.  The simplest way to convert code that sets
-\code{sys.exitfunc} is to import \module{atexit} and register the function
-that had been bound to \code{sys.exitfunc}.
+Note: the functions registered via this module are not called when
+the program is killed by a signal, when a Python fatal internal
+error is detected, or when \function{os._exit()} is called.
 
 \begin{funcdesc}{register}{func\optional{, *args\optional{, **kargs}}}
 Register \var{func} as a function to be executed at termination.  Any
@@ -47,7 +36,16 @@ chance to run the last exception to be raised is re-raised.
 
 \versionchanged[This function now returns \var{func} which makes it
                 possible to use it as a decorator without binding the
-		original name to \code{None}]{2.6}
+                original name to \code{None}]{2.6}
+\end{funcdesc}
+
+\begin{funcdesc}{unregister}{func}
+Remove a function \var{func} from the list of functions to be run at
+interpreter-shutdown.  After calling \function{unregister()},
+\var{func} is guaranteed not to be called when the interpreter
+shuts down.
+
+\versionadded{3.0}
 \end{funcdesc}
 
 
diff --git a/Doc/lib/libsys.tex b/Doc/lib/libsys.tex
index 7a8859b..ac161d9 100644
--- a/Doc/lib/libsys.tex
+++ b/Doc/lib/libsys.tex
@@ -218,19 +218,6 @@ It is always available.
   program when an error occurs.
 \end{funcdesc}
 
-\begin{datadesc}{exitfunc}
-  This value is not actually defined by the module, but can be set by
-  the user (or by a program) to specify a clean-up action at program
-  exit.  When set, it should be a parameterless function.  This
-  function will be called when the interpreter exits.  Only one
-  function may be installed in this way; to allow multiple functions
-  which will be called at termination, use the \refmodule{atexit}
-  module.  \note{The exit function is not called when the program is
-  killed by a signal, when a Python fatal internal error is detected,
-  or when \code{os._exit()} is called.}
-  \deprecated{2.4}{Use \refmodule{atexit} instead.}
-\end{datadesc}
-
 \begin{funcdesc}{getcheckinterval}{}
   Return the interpreter's ``check interval'';
   see \function{setcheckinterval()}.