signal handlers in a fork()ed child process when Python is compiled with
thread support. The bug was reported by Scott <scott@chronis.icgroup.com>.
What happens is that after a fork(), the variables used by the signal
module to determine whether this is the main thread or not are bogus,
and it decides that no thread is the main thread, so no signals will
be delivered.
The solution is the addition of PyOS_AfterFork(), which fixes the signal
module's variables. A dummy version of the function is present in the
intrcheck.c source file which is linked when the signal module is not
used.
Also grandly renamed.
Here's the new interface:
When WITH_READLINE is defined, two functions are defined:
- PyOS_GnuReadline (what used to be my_readline() with WITH_READLINE)
- PyOS_ReadlineInit (for Dave Ascher)
Always, these functions are defined:
- PyOS_StdioReadline (what used to be my_readline() without WITH_READLINE)
- PyOS_Readline (the interface used by tokenizer.c and [raw_]input().
There's a global function pointer PyOS_ReadlineFunctionPointer,
initialized to NULL. When PyOS_Readline finds this to be NULL, it
sets it to either PyOS_GnuReadline or PyOS_StdioReadline depending on
which one makes more sense (i.e. it uses GNU only if it is defined
*and* stdin is indeed a tty device).
An embedding program that has its own wishes can set the function
pointer to a function of its own design. It should take a char*
prompt argument (which may be NULL) and return a string *ending in a
\n character* -- or "" for EOF or NULL for a user interrupt.
--Guido van Rossum (home page: http://www.python.org/~guido/)
