Work around intrcheck.c's desire to pass 'PyErr_CheckSignals' to
'Py_AddPendingCall' by providing a (static) wrapper function that has the
right number of arguments.
For more comments, read the patches@python.org archives.
For documentation read the comments in mymalloc.h and objimpl.h.
(This is not exactly what Vladimir posted to the patches list; I've
made a few changes, and Vladimir sent me a fix in private email for a
problem that only occurs in debug mode. I'm also holding back on his
change to main.c, which seems unnecessary to me.)
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/)