[boost] Re: iostreams library review

5 Jun 2004


      "David Abrahams" <dave@boost-consulting.com> wrote in message
news:upt8fxspr.fsf@boost-consulting.com...
...
"Jonathan Turkanis" <technews@kangaroologic.com> writes:
...
"David Abrahams" <dave@boost-consulting.com> wrote in message
news:ubrk18u0m.fsf@boost-consulting.com...
...
"Jonathan Turkanis" <technews@kangaroologic.com> writes:
...
The caveat is that seeking with respect to stream positions -- 
i.e.
values of type traits_type::pos_type rather than
traits_type::off_type -- only works as expected for positions
which
are equivalent to integral offsets.
You lost me here.  What positions aren't?
positions that record an offset and a code conversion state.
Oh.  Yeah, I know nothing about that stuff.
You're better off that way -- trust me ;-)

<snip>
...
...
The offsetbuf could be defined like this (assuming a narrow
stream,
...
for simplicity):
class offsetbuf : public streambuf_facade<offset_filter> {
  public:
      offsetbuf(std::streambuf& sb, std::streamoff first,
std::streamoff last)
       {
           set_next(sb);
           open(offset_filter(first, last));
       }
  };
Here offset_filter is the filter I described before.
If you say so.
Well, I realize I wrote a bunch of stuff without explaning it, and the
documentation is not even available, so I shouldn't expect it to make
any sense. I guess my point was that it can be done with a few lines
of code.
...
Anyway, the library would be useful to me if it made
that possible.
Good. I think I'll add it as an example application, or maybe as part
of the core library.

Jonathan