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diff --git a/Mac/Demo/calldll/readme b/Mac/Demo/calldll/readme deleted file mode 100644 index 1e64dfe..0000000 --- a/Mac/Demo/calldll/readme +++ /dev/null @@ -1,48 +0,0 @@ -Preliminary notes/documentation for the calldll module, version 0.2. -==================================================================== - -Calldll allows you to call random C functions from python without writing any -C code. It is mainly meant to call MacOS toolbox routines for which no Python -wrapper module is available. It is also incomplete, in that only a few argument -types are currently supported. Please let me know which other argument types -you need, and/or whether you have any ideas on a general "escape" allowing people -to pass anything. - -The module exports three functions: -- symtable = getlibrary(libraryname) - Get a reference to import library libraryname. "InterfaceLib" is the most commonly - used one, containing most toolbox routines. The symbol table can be used - to lookup routines to be passed to newcall: "symtable.WaitNextEvent" will - return the address of routine WaitNextEvent. and so will "symtable['WaitNextEvent']". - The symtable is a mapping, so you can use keys() and len(...) to inspect it. -- symtable = getdiskfragment(file) - Load the specified file (given by fsspec or filename) and return a reference to - its symboltable. -- callable = newcall(routine, returntype, [argtype, ...]) - Return a callable object. You specify the C routine to be called (as explained above), - the type of the return value and the argument types. The resulting object can - be called from Python code in the normal way, and typechecking on arguments is - performed (but, of course, if you specify incorrect argument types in this call - you may well crash your machine). Printing a callable will give you a description - of the (C-) calling sequence. - -The C return value can be one of 'None', 'Byte', 'Short', 'Long', 'Pstring' (a pascal -string returned by address, copied to a Python string), 'Cobject' (a wrapper around a void -pointer), 'Handle' (a new handle, returned as a Res.Resource object) or 'OSErr' (which raises -MacOS.Error if non-zero). - -Arguments can be any of 'InByte', 'InShort', 'InLong', 'InString' (a python string, with the -address of the data passed to the C routine, so be careful!), 'InPstring' (a python string copied -to a Str255 and passed by address), 'InCobject', 'InHandle', 'OutByte' (storage is allocated for -a single byte, the address passed to C and the resulting value returned to Python), 'OutShort', -'OutLong', 'OutPstring' (again: storage pre-allocated and the address passed to C), 'OutCobject' -(storage for a void * is allocated, this void ** is passed to C and the resulting void * is -encapsulated in the Cobject returned) or 'OutHandle' (ditto, which means that this is usually *not* -what you use, you normally use 'InHandle' because most toolbox calls expect you to preallocate -the handle). - -All values to be returned (from the return value and the Out arguments) are collected. If there -aren't any None is returned, if there is one value this value is returned, if there are multiple -values a tuple is returned. - -There is test code in testcalldll.py, and a minimal example in samplecalldll.py. |