On Fri, Apr 8, 2011 at 7:43 AM, Jeff Flinn <TriumphSprint2000@hotmail.com> wrote:
Anders Knudby wrote:
Many thanks for the quick response. And apologies for being a total newbie, but how do I close the stream (and how do I check that it has been closed)? With normal iostreams I would just write "out.close();", out being the name of the stream. But that doesn't seem to be the way to do it for filtering_iostreams?!? And I would think it would close when it goes out of scope, but I haven't checked. Any help appreciated. I'm pleased it worked for you on Linux, but I'm largely stuck with Windows for the time being...

Can you post a complete small example demonstrating the problem? The destructor should close the stream. The docs for iostreams::stream shows a close method at http://www.boost.org/doc/libs/1_46_1/libs/iostreams/doc/index.html.

Please don't top post.


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Ok, here's my entire script. As mentioned in the comments it works fine if size=5e5. It also runs fine if size=5e6, but then the resulting file is corrupt (i.e. cannot be gunzipped with the gzip utility). Try it out. I'm using Visual Studio 2008 in a Windows XP machine.

#include <boost/iostreams/device/file.hpp>
#include <boost/iostreams/filter/gzip.hpp>
#include <boost/iostreams/filtering_stream.hpp>   

using namespace std;
namespace io = boost::iostreams;

int main()
    //Set filename
    string outfile = "c:/outfile.bin.gz";

    //Set filesize
    int size = int(5e6); // <- If I change this to '5e5' instead of '5e6', everything works just fine.
    //Declare memory block to be compressed to file
    char* memblock = new char [size];
    //Create a filtering_ostream out
    io::filtering_ostream out;

     //Assigns the gzip_compressor to out

     //Assigns out as a file sink
    //Write memblock to out
    out.write(memblock, size);
    //Clean up
    delete[] memblock;
    io::close(out); //Note, also tried 'out.close();', 'io::close(out, ios_base::out);' and 'close(out);'. Same result.

    return 0;

Anders Knudby