Hello.
I've been experiencing the following problem with the gzip_compressor
filter: It always writes data down the stream, regardless if any data
has been written to the filtering_stream.
Consider the following program:
--------------------------------------------------------
#include <iostream>
#include <fstream>
#include
#include
using namespace std;
using namespace boost;
int main()
{
ofstream file;
file.open("hello.gz",
ios_base::out | ios_base::app | ios_base::binary);
iostreams::filtering_streamboost::iostreams::output stream;
stream.push(iostreams::gzip_compressor());
stream.push(file);
return 0;
}
--------------------------------------------------------
If compiled as "test", the following behavior is observed:
$ ./test; ls -l hello.gz
-rw-r--r-- 1 count0 users 8 2005-10-30 19:51 hello.gz
$ ./test; ls -l hello.gz
-rw-r--r-- 1 count0 users 16 2005-10-30 19:51 hello.gz
$ ./test; ls -l hello.gz
-rw-r--r-- 1 count0 users 24 2005-10-30 19:51 hello.gz
That is, it always adds 8 bytes to the file, despite the fact that
nothing was written to the stream. To top things off, the data inside
the file isn't even recognizable by gzip:
$ gunzip hello.gz
gunzip: hello.gz: not in gzip format
When bzip2_compressor is used, this strange behavior doesn't happen, and
the file remains with 0 bytes.
I guess this is a bug, right?
I'm using boost 1.33.0 with GCC 4.0.1 in a GNU/Linux system.
Thanks for any help.
--
Tiago de Paula Peixoto
