id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
3447	After destruction binary_iarchive seeks to the end of file	Andrey Upadyshev <oliora@…>	Robert Ramey	"After destruction binary_iarchive seeks to the end of file. This is occured because boost::archive::basic_binary_iprimitive (the ancestor of binary_iarchive) calls std::basic_streambuf::sync in destructor. Calling 'sync' on a file streambuf seeks to the end of file.

This is bad, because it lead to skipping of unread input data!

I think calling 'sync' is a bad idea (and this call should be removed), but if it is necessary, then the documentation must clearly note that using a file streambuf with binary_iarchive skips to the end of the file.

----
Example:

{{{
std::ifstream is( ARCHIVE_FILE_NAME, std::ios::binary );

int i;
    
{
    boost::archive::binary_iarchive ar( is, boost::archive::no_header );
        
    ar >> i;
        
    std::cout << ""Pos after read: "" << is.tellg() << std::endl;
}

std::cout << ""Pos after dtor: "" << is.tellg() << std::endl;
}}}

Output:
{{{
Pos after read: 4
Pos after dtor: 11
}}}
(sizeof(int) is 4, archive file length is 11)"	Bugs	new		serialization	Boost 1.39.0	Problem		sync file stream basic_binary_iprimitive archive binary_iarchive serialization