From: Jeffrey Faust (jeff_at_[hidden])
Date: 2008-04-16 16:22:53
We've discovered an issue Boost has writing and reading wide character
strings (wchar_t* and std::wstrings) to non-wide character file streams
(std::ifstream and std::ofstream). The issue stems from the fact that
wide characters are written and read as a sequence of characters (in
text_oarchive_impl.ipp and text_iarchive_impl.ipp, respectively). For
text streams, an EOF character terminates the reading of a file on
Windows. Some wide characters have EOF (value = 26 decimal) as one of
the bytes so reading that byte causes early termination of the read. We
have worked around the issue by deriving our own input and output
archives from text_i|oarchive_impl<Archive> and overriding
load_override() and save_override for std::wstring and wchar_t*. Our
implementation just sequences through the wide characters and writes
them 1 by 1 as wchar_t to the archive. This isn't very elegant and is
even less readable in the file than the current implementation but does
resolve the problem.
I looked at both Boost 1.34.1 and 1.35 and didn't see a difference in
the implementation here so I'm assuming 1.35 still has the issue. I've
been working with 1.34.1. Is this a known issue? Does 1.35 solve it in
some other subtle way? Is there a better way that doesn't require us to
derive our own streams? If not, is there a more elegant way of
implementing the reading and writing of wide characters ourselves?
Thanks in advance.
Jeff Faust