On 2010-06-11 09:34:27 +0200, Roland Bock said:

Kraus Philipp wrote:

...

Hi,

on my previous posting I have another questing:

I create my compression stream with

bio::filtering_streambuf< bio::input > l_deflate; switch (m_compress) { case gzip : l_deflate.push( bio::gzip_compressor() ); break; case bzip2 : l_deflate.push( bio::bzip2_compressor() ); break; }

For a single file I push it to zip with:

l_deflate.push( bio::file_source(p_str1, BOOST_IOS::binary) );

I need a concatination for two files like: l_deflate.push( bio::file_source(p_str1, BOOST_IOS::binary) ); l_deflate.push( bio::file_source(p_str2, BOOST_IOS::binary) );

for unix shell I do this with:

cat file1.txt > tozip.txt cat file2.txt >> tozip.txt

How I can push a concatinated file to the deflate stream buffer?

Thanks

Phil

Hi,

I see two options:

a) You write a new multi_file_source class which can any number of input files.

b) Instead of working with a source, you could work with a sink at the other end of the pipeline. Then just copy the content of the two files into the stream.

Hi, I think I would like to use the second idea, but how I can do this? Thx Phil

Am 13.06.2010 um 15:41 schrieb Roland Bock:

Philipp Kraus wrote:

...

On 2010-06-11 09:34:27 +0200, Roland Bock said:

...

Kraus Philipp wrote:

...

Hi,

on my previous posting I have another questing:

I create my compression stream with

bio::filtering_streambuf< bio::input > l_deflate; switch (m_compress) { case gzip : l_deflate.push( bio::gzip_compressor() ); break; case bzip2 : l_deflate.push( bio::bzip2_compressor() ); break; }

For a single file I push it to zip with:

l_deflate.push( bio::file_source(p_str1, BOOST_IOS::binary) );

I need a concatination for two files like: l_deflate.push( bio::file_source(p_str1, BOOST_IOS::binary) ); l_deflate.push( bio::file_source(p_str2, BOOST_IOS::binary) );

for unix shell I do this with:

cat file1.txt > tozip.txt cat file2.txt >> tozip.txt

How I can push a concatinated file to the deflate stream buffer?

Thanks

Phil

Hi,

I see two options:

a) You write a new multi_file_source class which can any number of input files.

b) Instead of working with a source, you could work with a sink at the other end of the pipeline. Then just copy the content of the two files into the stream.

Hi,

I think I would like to use the second idea, but how I can do this?

Thx

Phil Hi,

currently, all your examples are using filtering input streams with a source. For concatination and compression I would use a filtering output stream and a sink (for instance a file sink).

Then you open an ifstream for the first file and copy its content into the filtering output stream. Then you open an ifstream for the second file and copy its content into the filtering output stream.

Thanks that was a very big hint. My code is now: bio::basic_null_sink<char> l_out; bio::counter l_counter; bio::filtering_streambuf< bio::output > l_deflate; l_deflate.push( bio::gzip_compressor() ); l_deflate.push( boost::ref(l_counter) ); l_deflate.push( l_out ); std::ifstream l_file( p_str1.c_str(), std::ifstream::in | std::ifstream::binary ); bio::copy( l_file, l_deflate ); l_file.close(); l_file.open( p_str2.c_str(), std::ifstream::in | std::ifstream::binary ); ===> bio::copy( l_file, l_deflate ); <==== error l_file.close(); It works perfectly, except the second copy. On this line I get a "segmentation fault" (sorry I can't use the debugger, because the code runs on another system). Thanks a lot Phil

Am 15.06.2010 um 18:08 schrieb Roland Bock:

You could try to use std::copy like this (untested code):

copy(istreambuf_iterator<char>(l_file), istreambuf_iterator<char>(), ostreambuf_iterator<char>(l_deflate));

I have a problem with the thrid parameter, if I change it to std::cout there're no problems, but my l_deflate is a bio::filtering_streambuf< bio::output > and I can't convert it to a std::ostreambuf_iterator<char> for the std::copy. I get the message: no matching function for call to 'std::ostream_iterator

::ostream_iterator (boost::iostreams::filtering_streambuf&)' Do you have any idea? Thanks

Am 15.06.2010 um 21:37 schrieb Steven Watanabe:

AMDG

Kraus Philipp wrote:

...

Am 15.06.2010 um 18:08 schrieb Roland Bock:

...

You could try to use std::copy like this (untested code):

copy(istreambuf_iterator<char>(l_file), istreambuf_iterator<char>(), ostreambuf_iterator<char>(l_deflate));

I have a problem with the thrid parameter, if I change it to std::cout there're no problems, but my l_deflate is a bio::filtering_streambuf< bio::output > and I can't convert it to a std::ostreambuf_iterator<char> for the std::copy. I get the message:

no matching function for call to 'std::ostream_iterator

...

::ostream_iterator (boost::iostreams::filtering_streambuf&)'

Do you have any idea?

Use std::ostreambuf_iterator instead std::ostream_iterator.

Thanks, now I can finished my normalized compression distance with Boost :-) (I hope it works on MS systems also) Many thanks to all Phil

Am 15.06.2010 um 18:54 schrieb Steven Watanabe:

AMDG

Kraus Philipp wrote:

...

Thanks that was a very big hint.

My code is now:

bio::basic_null_sink<char> l_out; bio::counter l_counter; bio::filtering_streambuf< bio::output > l_deflate;

l_deflate.push( bio::gzip_compressor() ); l_deflate.push( boost::ref(l_counter) ); l_deflate.push( l_out );

std::ifstream l_file( p_str1.c_str(), std::ifstream::in | std::ifstream::binary ); bio::copy( l_file, l_deflate ); l_file.close();

l_file.open( p_str2.c_str(), std::ifstream::in | std::ifstream::binary ); ===> bio::copy( l_file, l_deflate ); <==== error l_file.close();

It works perfectly, except the second copy. On this line I get a "segmentation fault" (sorry I can't use the debugger, because the code runs on another system).

I'm guessing that the problem is that copy closes the sink.

Yes: http://boost.sourceforge.net/libs/iostreams/doc/functions/copy.html The function template copy reads data from a given model of Source and writes it to a given model of Sink until the end of stream is reached. It then closes both components, using the function template close, and returns the number of characters written.