My command line is this (powershell):
$7z ="`"c:\Program Files\7-Zip\7z.exe`""
&$7z a -r -ttar -bd -so . | &$7z a -r -txz -bd $archive -si
The produced archive file indeed contains a tar file, but that tar file is corrupt.
Note, that breaking the pipe into two commands works correctly:
&$7z a -r -ttar -bd ${archive}.tmp .
&$7z a -r -txz -bd $archive ${archive}.tmp
The produced archive is perfectly valid.
So, what is wrong with my pipeline?
(I am using Powershell)