Setting Tar compression level in Win10-CodePudding

I created a powershell command in order to compress mdb files from a certain folder. The structure looks like this:

C:\Projects\MySoftware\templates\A\a.mdb
C:\Projects\MySoftware\templates\B\b.mdb
C:\Projects\MySoftware\templates\C\c.mdb

Basically I want that my archive must contains the directories with "templates" as root node. So:

templates\A\a.mdb
templates\B\b.mdb
templates\C\c.mdb

And in PowerShell

powershell -Command "$pa = 'C:\Projects'; Set-Location C:\Projects\MySoftware\; gci -Path templates -Recurse -Include *.mdb  | sort LastWriteTime  | ForEach-Object {  cd 'C:\Projects\MySoftware\'; $fn = $_.Fullname; tar rf BASetupUpdate.tgz $($fn.Replace('C:\Projects\MySoftware\','')) }"

The tar creates correctly the archive but without compression. I'm struggling with command line and help in order to set the compression level.

CodePudding user response：

You need to add the z option to compress, which cannot be used with r, only c. You would need to make a list of all the things you want to put in the tar file, and use a single invocation of the tar command with all of those names. You cannot incrementally add files to a compressed tar.gz (or .tgz if you prefer) archive. So something like:

tar -czf archive.tgz file1 file2 ... filen

As for the compression level, you can add --option gzip:compression-level=9. However to start, you should leave it at the default level and see if that meets your needs. Higher compression levels can take much more time for a small reduction in size.