How to write partial of a buffer which was returned from a C function to a file?

[jfong at ms4.hinet.net]

This C function returns a buffer which I declared it as a ctypes.c_char_p. The buffer has size 0x10000 bytes long and the valid data may vary from a few bytes to the whole size.

In every call I know how much the valid data size is, but I suppose I can't use slice to get it because there may be zero byte in it. What to do?


Best Regards,
Jach Fong