I work on several projects that have initialization requirements that need to grab control after Py_Initialize(), but before any user code runs (via input, script, -c, etc...). Note that these are Python clones that take advantage of an installed python (using its $prefix/lib/pythonx.x/*.py and site-packages/*) We could use PyImport_AppendInittab("sitecustomize",initsitecustomize); But if there already IS customization in sitecustomize.py, I've blown it away (and have to look it up and force an import). And if someone uses the -S flag, I'm screwed. I propose a hook styled after Py_AtExit(func) called Py_AtInit(func) which maintains a list of functions that are called in Py_Initialize right after main and site initializations. If the hook isn't used, then the cost is a single extra function call at initialization. Here's a spurious example: A customer wants a version of python that has all the math functions and his extensions to act like builtins... I would write (without refcnt or error checks ;-): #include "Python.h" static void after_init(void) { PyObject *builtin,*builtin_dict,*math,*math_dict,*user,*user_dict; builtin = PyImport_ImportModule("__builtin__"); builtin_dict = PyModule_GetDict(builtin); math = PyImport_ImportModule("math"); math_dict = PyModule_GetDict(math); user = PyImport_ImportModule("user"); user_dict = PyModule_GetDict(math); PyDict_Update(builtin_dictionary, math_dict); PyDict_Update(builtin_dictionary, user_dict); } int main(int argc, char** argv) { PyImport_AppendInittab("user",inituser); Py_AtInit(after_init); return Py_Main(argc, argv); } voila! An extended Python with new builtins. I actually want this to do some MPI initialization to setup a single user prompt with broadcast which has to run after Py_Initialize() but before the import of readline. I've attached a copy of the patch (also going to patches at sf.net) Pat -- Patrick Miller | (925) 423-0309 | http://www.llnl.gov/CASC/people/pmiller Son, when you grow up you will know who I really am. I am just a child like you who has been forced to act responsibly. -- Rod Byrnes Index: dist/src/Include/pythonrun.h =================================================================== RCS file: /cvsroot/python/python/dist/src/Include/pythonrun.h,v retrieving revision 2.62 diff -c -r2.62 pythonrun.h *** dist/src/Include/pythonrun.h 13 Feb 2003 22:07:52 -0000 2.62 --- dist/src/Include/pythonrun.h 30 Apr 2003 22:04:13 -0000 *************** *** 75,80 **** --- 75,81 ---- PyAPI_FUNC(void) PyErr_Display(PyObject *, PyObject *, PyObject *); PyAPI_FUNC(int) Py_AtExit(void (*func)(void)); + PyAPI_FUNC(int) Py_AtInit(void (*func)(void)); PyAPI_FUNC(void) Py_Exit(int); Index: dist/src/Python/pythonrun.c =================================================================== RCS file: /cvsroot/python/python/dist/src/Python/pythonrun.c,v retrieving revision 2.193 diff -c -r2.193 pythonrun.c *** dist/src/Python/pythonrun.c 22 Apr 2003 11:18:00 -0000 2.193 --- dist/src/Python/pythonrun.c 30 Apr 2003 22:04:16 -0000 *************** *** 106,111 **** --- 106,135 ---- return flag; } + #define NINITFUNCS 32 + static void (*initfuncs[NINITFUNCS])(void); + static int ninitfuncs = 0; + + int Py_AtInit(void (*func)(void)) + { + if (ninitfuncs >= NINITFUNCS) + return -1; + if (!func) + return -1; + initfuncs[ninitfuncs++] = func; + return 0; + } + + static void initinitialize(void) + { + int i; + for(i=0;i<ninitfuncs;++i) { + initfuncs[i](); + if (PyErr_Occurred()) + Py_FatalError("Py_AtInit: initialization error"); + } + } + void Py_Initialize(void) { *************** *** 182,190 **** --- 206,217 ---- initsigs(); /* Signal handling stuff, including initintr() */ initmain(); /* Module __main__ */ + if (!Py_NoSiteFlag) initsite(); /* Module site */ + initinitialize(); /* Extenstion hooks */ + /* auto-thread-state API, if available */ #ifdef WITH_THREAD _PyGILState_Init(interp, tstate); *************** *** 1418,1423 **** --- 1445,1451 ---- #endif /* MS_WINDOWS */ abort(); } + /* Clean up and exit */