Decompression (SharpZipLib )

  • Thread starter Thread starter csharpula csharp
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csharpula csharp

Hello ,

In case someone uses SharpZipLib :

I am using SharpZipLib in order to compress and decompress gzip files. I
decompress a fie which was compressed with SharpZipLib code in a
following way:

//args[0] - gzip file ,args[1] - folder to extract to

TarArchive archive = null;

using (Stream s = new GZipInputStream(File.OpenRead(args[0])))

{

archive = TarArchive.CreateInputTarArchive(s);

if (!Directory.Exists(args[1]))

{

Directory.CreateDirectory(args[1]);

}

archive.ExtractContents(args[1]);



But I get the following error (for inpur that was also compressed by
SharpZipLib code) : Error GZIP header, first magic byte doesn't match.

Why is that? How can I solve this?

Thanks!
 
But I get the following error (for inpur that was also compressed by
SharpZipLib code) : Error GZIP header, first magic byte doesn't match.

Why is that? How can I solve this?
Click to expand...

Have you considered asking in the SharpZipLib forums? I've been there in the
past and they were pretty helpful.

I don't use GZip, so I can't help you.
 
csharpula said:
In case someone uses SharpZipLib :

I am using SharpZipLib in order to compress and decompress gzip files. I
decompress a fie which was compressed with SharpZipLib code in a
following way:

//args[0] - gzip file ,args[1] - folder to extract to

TarArchive archive = null;

using (Stream s = new GZipInputStream(File.OpenRead(args[0])))

{

archive = TarArchive.CreateInputTarArchive(s);

if (!Directory.Exists(args[1]))

{

Directory.CreateDirectory(args[1]);

}

archive.ExtractContents(args[1]);



But I get the following error (for inpur that was also compressed by
SharpZipLib code) : Error GZIP header, first magic byte doesn't match.

Why is that? How can I solve this?
Click to expand...

The error message tell you that the first two bytes of the files
is not what it should be to be avalid GZIP file.

Can you create a simple example of code that creates the
file and code that attempts to read the file ?

Then I am sure that we can find the problem.

Arne
 
That's how I compress (and I wrote in previous mail how I decompress)
Why do I still get this error on decompression if I compress this way?

try
{

byte[] dataBuffer = new byte[4096];

TarArchive archive = null;

using (Stream tarS = new
TarOutputStream(File.Create(_filePath)))
{

archive = TarArchive.CreateOutputTarArchive(tarS);



foreach (string file in _filesList)
{
TarEntry entry =
TarEntry.CreateEntryFromFile(file);
archive.WriteEntry(entry, true);
}

archive.Close();

using (Stream gzipS = new
GZipOutputStream(File.Create(_filePath + ".gz")))
{
using (FileStream fs = File.OpenRead(_filePath))
{
StreamUtils.Copy(fs, gzipS, dataBuffer);
}

}



}
 
csharpula said:
That's how I compress (and I wrote in previous mail how I decompress)
Click to expand...
try
{

byte[] dataBuffer = new byte[4096];

TarArchive archive = null;

using (Stream tarS = new
TarOutputStream(File.Create(_filePath)))
Click to expand...

I am sure that I could copy those code fragments into
source files and build the stuff around necessary to make
them compilable programs, if I were willing to spend time
on it.

But it is not my problem, so ...

Arne
 
csharpula csharp said:
That's how I compress (and I wrote in previous mail how I decompress)
Why do I still get this error on decompression if I compress this way?

try
{

byte[] dataBuffer = new byte[4096];

TarArchive archive = null;

using (Stream tarS = new
TarOutputStream(File.Create(_filePath)))
{

archive = TarArchive.CreateOutputTarArchive(tarS);



foreach (string file in _filesList)
{
TarEntry entry =
TarEntry.CreateEntryFromFile(file);
archive.WriteEntry(entry, true);
}

archive.Close();

using (Stream gzipS = new
GZipOutputStream(File.Create(_filePath + ".gz")))
{
using (FileStream fs = File.OpenRead(_filePath))
{
StreamUtils.Copy(fs, gzipS, dataBuffer);
}

}



}
Click to expand...


I would try closing the "using (Stream tarS)" before doing the gzip process.
You are done with the tar stream at that point anyways.
 
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