Extract a tar.gz file in C# · onearchive cookbook

Call Archive.Extract with the .tar.gz file and a target folder: the gzip layer and the tar inside are both handled. The program below extracts the zlib source release, a tar.gz you can download to try it.

Terminal

dotnet new console -o ExtractTarGz && cd ExtractTarGz
dotnet add package RecursiveAI.OneArchive --version 1.0.0
curl -L -o zlib-1.3.1.tar.gz https://github.com/madler/zlib/archive/refs/tags/v1.3.1.tar.gz

Put this in Program.cs and run dotnet run:

using RecursiveAI.OneArchive;
 
using (var archive = Archive.Open("zlib-1.3.1.tar.gz"))
{
    Console.WriteLine($"{archive.Entries.Count} entries");
    foreach (var e in archive.Entries.Take(4))
        Console.WriteLine($"  {e.Kind,-9} {e.Size,7:N0}  {e.Name}");
 
    // Read one file without extracting the rest.
    using var readme = archive.OpenEntry(archive.Find("zlib-1.3.1/README")!);
    Console.WriteLine(new StreamReader(readme).ReadLine());
}
 
Archive.Extract("zlib-1.3.1.tar.gz", "src");
int count = Directory.GetFiles("src", "*", SearchOption.AllDirectories).Length;
Console.WriteLine($"extracted {count} files to src/");

Text

296 entries
  Directory       0  zlib-1.3.1
  Directory       0  zlib-1.3.1/.github
  Directory       0  zlib-1.3.1/.github/workflows
  File        2,402  zlib-1.3.1/.github/workflows/cmake.yml
ZLIB DATA COMPRESSION LIBRARY
extracted 257 files to src/

The format comes from the bytes, so .tgz, .tar.xz, .tar.zst, .tar.bz2, .tar.lz4 and a plain .tar extract with the same call. Paths that would climb out of src/ and links that point outside it are refused (Extract untrusted archives safely).

Limits

Owners aren’t restored. Permissions and modification times are (RestorePermissions and RestoreTimes, both on by default), but there is no chown from managed code; each entry still carries its owner ids and names.
Reading one file from a .tar.gz reads up to it. gzip can’t seek, so OpenEntry decompresses the archive from the start; for many random reads, extract first or use zip.

To create a tar.gz, Archive.Create("backup.tar.gz").Add("folder/").Save() picks the format from the extension, as Getting started shows.