How do I create my own ostream/streambuf?

Question

For educational purposes I want to create a ostream and stream buffer to do:

1. fix endians when doing << myVar;
2. store in a deque container instead of using std:cout or writing to a file
3. log extra data, such as how many times I did <<, how many times I did .write, the amount of bytes I written and how many times I flush(). But I do not need all the info.

I tried overloading but failed horribly. I tried overloading write by doing

ostream& write( const char* s, streamsize n ) 

in my basic_stringstream2 class (I copied paste basic_stringstream into my cpp file and modified it) but the code kept using basic_ostream. I looked through code and it looks like I need to overload xsputn (which isn't mention on this page http://www.cplusplus.com/reference/iostream/ostream ) but what else do I need to overload? and how do I construct my class (what does it need to inherit, etc)?

Answer 1

The canonical approach consists in defining your own streambuf. You should have a look at:

• Angelika LAnger's articles on IOStreams derivation
• James Kanze's articles on filtering streambufs
• boost.iostream for examples of application