I'm using GNU tar 1.30 from an RHEL-derived distro, which doesn't know about --zstd.
This is not a bug, however when I try to create archive.tar.zst there is no clue that it didn't work. tar 1.30 silently creates uncompressed output. Specifically, if the newly created filename is unknown to suffix.c::find_compression_suffix then no compression is applied and no warning emitted. I appreciate for --extract --auto-compress that such a warning could be considered noise, but when using --create for a brand new archive it would be helpful to tell the user that the suffix is unrecognised. Steps to repro: $ tar --version tar (GNU tar) 1.30 $ tar cfva test.tar.zst t*.c tar.c transform.c $ file test.tar.zst test.tar.zst: POSIX tar archive (GNU) Expected output: $ tar cfva test.tar.zst t*.c tar: Unknown auto-compress suffix "zst", proceeding with no compression tar.c transform.c Cheers, Phil
