All commands tested on Mac OS Monterey / Jan 05, 2022

Tar Append Examples

How to append a file to an existing tar archive

Add new-file.txt to the existing archive files.tar.
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How to append files of a specific filetype to an existing tar archive

Add all the *.txt files in a directory to the existing files.tar archive.
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How to append a directory to an existing tar archive

Add a directory ~/some-other-directory to an existing files.tar archive.
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