boost-iostreams

问题 I am new to boost::iostreams so this might be trivial: Assuming namespace io = boost::iostreams; this works io::filtering_ostream out(std::cout); out << "some\nstring\n"; and this works std::string result; io::filtering_ostream out(io::counter() | io::back_inserter(result)); out << "some\nstring\n"; yet this does not compile io::filtering_ostream out(io::counter() | std::cout); out << "some\nstring\n"; How do you pipe into std::cout ? 回答1: Wrapping std::cout with boost::ref worked for me: io:

问题 I use Boost::iostreams to write simultaneously to my console and a file. When i use eclipse to debug(with gdb of course), i receive a warning which says RTTI symbol not found for one of the classes that i am using from Boost::iostreams. Here is the minimal code to reproduce the problem. #ifndef BOOST_IO_STREAM_H_ #define BOOST_IO_STREAM_H_ #include <fstream> #include <boost/iostreams/tee.hpp> #include <boost/iostreams/stream.hpp> using boost::iostreams::tee_device; using boost::iostreams:

问题 Is there some magic required to obtain a "zlib sync flush" when using boost::iostreams::zlib_compressor ? Just invoking flush on the filter, or strict_sync on a filtering_ostream containing it doesn't see to do the job (ie I want the compressor to flush enough that the decompressor can recover all the bytes consumed by the compressor so far, without closing the stream). Looking at the header, there seem to be some "flush codes" defined (notably a sync_flush ) but it's unclear to me how they

问题 Is there some magic required to obtain a "zlib sync flush" when using boost::iostreams::zlib_compressor ? Just invoking flush on the filter, or strict_sync on a filtering_ostream containing it doesn't see to do the job (ie I want the compressor to flush enough that the decompressor can recover all the bytes consumed by the compressor so far, without closing the stream). Looking at the header, there seem to be some "flush codes" defined (notably a sync_flush ) but it's unclear to me how they

问题 So normaly I do stuff like: std::ifstream stream; int buff_length = 8192; boost::shared_array<char> buffer( new char[buff_length]); stream.open( path.string().c_str(), std::ios_base::binary); while (stream) { stream.read(buffer.get(), buff_length); //boost::asio::write(*socket, boost::asio::buffer(buffer.get(), stream.gcount())); } stream.close(); I wonder how to read into unsigned char buffer ( boost::shared_array<unsigned char> buffer( new unsigned char[buff_length]); ) 回答1: In a simplest

问题 Just trying to compress a string with bzip2 so that I can send it over a pipe with ReadFile. The following line earns me the following compile error. in.push(uncompressed_string); Error 6 error C2027: use of undefined type 'boost::STATIC_ASSERTION_FAILURE' c:\program files (x86)\boost\boost_1_47\boost\iostreams\chain.hpp 488 1 Agent boost::iostreams::filtering_streambuf<boost::iostreams::input> in; ostringstream uncompressed_string; ostringstream compressed_string; uncompressed_string << buf;

问题 I'm having a problem with the zlib libraries in boost under VS 2010. I built the libraries and the appropriate dlls/libs were generated in the boost/stage/lib folder. I added the .dlls into my programs debug folder and linked in the matching.lib. But I'm running into problems when I actually try to use the zlib streams. Heres an example: #include <cstring> #include <string> #include <iostream> #include <boost\iostreams\filter\gzip.hpp> #include <boost\iostreams\filtering_streambuf.hpp>

问题 My aim is to send a data to several streams. It is possible by using boost::tee. But I want to write a wrapper with variadic template for using several streams. The problem is that I need an implicit convertation from descendant struct to ancestor struct. Or something like that. #include <boost/iostreams/tee.hpp> #include <boost/iostreams/stream.hpp> #include <fstream> #include <iostream> using namespace std; namespace bio = boost::iostreams; using bio::tee_device; using bio::stream; template

问题 I use Boost.Serialization to serialize a std::map. The code looks like this void Dictionary::serialize(std::string & buffer) { try { std::stringstream ss; boost::archive::binary_oarchive archive(ss); archive << dict_; buffer = ss.str(); } catch (const std::exception & ex) { throw DictionaryException(ex.what()); } } void Dictionary::deserialize(const char * const data, int length) { try { namespace io = boost::iostreams; io::array_source source(data, length); io::stream<io::array_source> in

问题 I am very new to the memory mapping and trying to understand memory mapped files to use them in my project(linux based). My requirement is to write & then read from memory mapped files. I wrote a sample program which only writes and it works fine but i have a few very basic doubts as i do not understand this funda of memory mapping properly. #include <unordered_map> #include <boost/iostreams/device/mapped_file.hpp> using namespace boost::interprocess; using namespace std; typedef unordered