Dan wrote (2020-10-23):

 DR> On 23 Oct 2020, 11:11a, Michael Dukelsky said the following...

 MD>> Sorry, but I stopped supporting RNtrack. Its last version was
 MD>> 2.1.10. Try it,maybe it will help.

 DR> I just tried to unarchive it, and I'm getting:

 DR> tar -xvzf rntrack-1_1_10-src.tar.bz2

 DR> gzip: stdin: not in gzip format
 DR> tar: Child returned status 1
 DR> tar: Error is not recoverable: exiting now

the -z parameter is for gzip files, but this is a bzip2 file. Use the -j parameter for bzip2 files:

 tar -xvjf

newer tar versions do recognize the compression automatically. This should als work:

 tar -xvf

or

 tar -xvaf

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