ctypes mmf 예제

import sys
import mmap
import time
from ctypes import *
from ctypes.wintypes import BOOL, DWORD, HANDLE, LPCWSTR, LPCVOID, LPVOID
 
 
if __name__ == "__main__":
    print("Python {:s} on {:s}".format(sys.version, sys.platform))
    FILE_MAP_ALL_ACCESS = 0x000F001F
    INVALID_HANDLE_VALUE = -1
    SHMEMSIZE = 0x100
    PAGE_READWRITE = 0x04
    
    kernel32_dll = windll.kernel32
    msvcrt_dll = cdll.msvcrt
    
    create_file_mapping_func = kernel32_dll.CreateFileMappingW
    create_file_mapping_func.argtypes = (HANDLE, LPVOID, DWORD, DWORD, DWORD, LPCWSTR)
    create_file_mapping_func.restype = HANDLE
    
    map_view_of_file_func = kernel32_dll.MapViewOfFile
    map_view_of_file_func.argtypes = (HANDLE, DWORD, DWORD, DWORD, c_ulonglong)
    map_view_of_file_func.restype = LPVOID
    
    memcpy_func = msvcrt_dll.memcpy
    memcpy_func.argtypes = (c_void_p, c_void_p, c_size_t)
    memcpy_func.restype = LPVOID
    
    rtl_copy_memory_func = kernel32_dll.RtlCopyMemory
    rtl_copy_memory_func.argtypes = (LPVOID, LPCVOID, c_ulonglong)
    
    unmap_view_of_file_func = kernel32_dll.UnmapViewOfFile
    unmap_view_of_file_func.argtypes = (LPCVOID,)
    unmap_view_of_file_func.restype = BOOL
    
    memcpy_func = msvcrt_dll.memcpy
    memcpy_func.argtypes = (c_void_p, c_void_p, c_size_t)
    memcpy_func.restype = LPVOID
    
    rtl_copy_memory_func = kernel32_dll.RtlCopyMemory
    rtl_copy_memory_func.argtypes = (LPVOID, LPCVOID, c_ulonglong)
    
    unmap_view_of_file_func = kernel32_dll.UnmapViewOfFile
    unmap_view_of_file_func.argtypes = (LPCVOID,)
    unmap_view_of_file_func.restype = BOOL
    
    close_handle_func = kernel32_dll.CloseHandle
    close_handle_func.argtypes = (HANDLE,)
    close_handle_func.restype = BOOL
    
    get_last_error_func = kernel32_dll.GetLastError
    getch_func = msvcrt_dll._getch
    
    file_mapping_name_ptr = c_wchar_p("MyFileMappingObject")
    msg = "Message from Python(ctypes) process"
    msg_ptr = c_wchar_p(msg)
    mapping_handle = create_file_mapping_func(INVALID_HANDLE_VALUE, 0, PAGE_READWRITE, 0, SHMEMSIZE, file_mapping_name_ptr)
 
    print("Mapping object handle: 0x{:016X}".format(mapping_handle))
    if not mapping_handle:
        print("Could not open file mapping object: {:d}".format(get_last_error_func()))
        raise WinError()
        
    mapped_view_ptr = map_view_of_file_func(mapping_handle, FILE_MAP_ALL_ACCESS, 0, 0, SHMEMSIZE)
    
    print("Mapped view addr: 0x{:016X}".format(mapped_view_ptr))
    if not mapped_view_ptr:
        print("Could not map view of file: {:d}".format(get_last_error_func()))
        close_handle_func(mapping_handle)
        raise WinError()    
 
    
    byte_len = len(msg) * sizeof(c_wchar)
    print("Message length: {:d} chars ({:d} bytes)".format(len(msg), byte_len))
    
    memcpy_func(mapped_view_ptr, msg_ptr, byte_len)
    rtl_copy_memory_func(mapped_view_ptr, msg_ptr, byte_len)
    
    unmap_view_of_file_func(mapped_view_ptr)
    close_handle_func(mapping_handle)
 
  
    shmem = mmap.mmap(0, 256, "MyFileMappingObject_ctypes", mmap.ACCESS_WRITE)
    shmem.write(b"Message Python process")
 
    shmem.close()
    
    print("Hit a key to exit...")
    getch_func()
 

출처: https://stackoverflow.com/questions/48788549/python-ctypes-oserror-exception-access-violation-writing-0xfffffffffa1c001