> I suspect you need to use "wb" here. The zlib.h header says
> ZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode));
Thanks. As you and Paul suggested, the problem is the text/binary mode
for opening the file. I thought that the text mode (with 't' suffix) was only
enabled if explicitely specified, but it is the default; hence MSVC translates
'\\n' into '\\r\\n' and corrupts the compressed data. So, under MSVC, you
really need to specify 'b' explicitely.
> Strange that they would allow these other extensions to the mode
> string and not automatically open the stream in binary mode (since it
> would seem to be required) whether or not "b" is specified.
> Is Octave failing to open a stream in binary mode when it should?
When saving in compressed text form, the gzFile stream is opened without
the 'b' suffix (mode does not contain std::ios::binary). I proposed the following
patch, which forces binary mode on compressed streams under Win32
except Cygwin.
Michael.
Index: src/zfstream.cc =================================================================== RCS file: /cvs/octave/src/zfstream.cc,v retrieving revision 1.2 diff -c -p -r1.2 zfstream.cc *** src/zfstream.cc 26 Apr 2005 19:24:35 -0000 1.2 --- src/zfstream.cc 8 Dec 2006 10:24:49 -0000 *************** gzfilebuf::open_mode(std::ios_base::open *** 187,193 **** --- 187,195 ---- // Mode string should be empty for invalid combination of flags if (strlen(c_mode) == 0) return false; + #if ! defined (__WIN32__) || defined (__CYGWIN__) if (testb) + #endif strcat(c_mode, "b"); return true; }