basic_filebuf question

[Stephan Buys]

Hi all,

I am trying to implement a Binary Patching program. In order to create my 
patch files I need to search for patterns in files. I am trying to optimise 
the algorithms and need access to the filebuffers' memory.

I use a normal std::ifstream for file input and can then the buffer by 
calling MyFile.rdbuf().

I have thought about creating my own basic_filebuf class with Search 
implemented and then setting it by using MyFile.rdbuf(&MyBuf). According to 
documentation I read (C++ Programming Language) this should make my ifstream 
use my new buffer. This version of the std::basic_ios (I think) is not 
implemented it seems.

Any idea? I want to direct access to the buffers as I can then use routines 
like memcmp (which is optimised) to do pattern matching. 

Any pointers or slaps on the head would be greatly appreciated!

Regards,
Stephan Buys