lemme just write a python script to talk to a cross-platform c++ program through shared memory on win32.
this certainly won't be an infinite nightmare, right?
I'm using pywin32 which doesn't give me the ability to distinguish between opening a named shared memory area and creating one, so it succeeds but just because it creates a new shared memory area for me full of nothing
guess I'm gonna have to switch to ctypes!
the C++ code calls CreateFileMappingA( INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE, 0, memory_map_size, "DWD_GAMELINK_MMAP_R4");
and then on python, I call
OpenFileMappingA(FILE_MAP_ALL_ACCESS, False, "DWD_GAMELINK_MMAP_R4") and get a File Not Found error.
hmmm.
it was unicode!
unicode: the DNS of filename problems
yeah I don't think pywin32's mmapfile lets you use an ASCII filename, and windows apparently matches named shared memory by the bytes of the name, not the value of the characters. so a unicode "foo" and an ascii "foo" are different mappings
or maybe it was just that I was calling OpenFileMappingA with a unicode string, which is obviously wrong.
That still doesn't explain why pywin32 wasn't working, and since I've already written the ctypes equivalent, I'm not gonna look into it
cancel the celebrations, I've mapped the named shared memory supposedly properly but when I read from it I get a 0.
it should be a 4. So this isn't working
I'm definitely opening the mapping, though. if I change the name to "foobar" I get a FileNotFound error. HMMM
ugh I'm probably gonna have to write some C++ code to get it working, and then once I know what's wrong, I can translate that to python
I used cheat engine to explore the memory regions of my python script, and it DOES have an appropriately-sized mapped region, but it similarly seems to be full of zeros.
