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pipe - create tar file from stdin

I want to backup mysql to a tape on-the-fly. Some like

mysqldump|tar --filename=mysqlbackup.sql > /dev/tape

I want the tape has content a tar file and this file has content "mysqldump.sql"

So a command "tar -t < /dev/tape" should output

mysqldump.sql

I don't want at first save mysqldump to file, because I have no space and IO resources. I want to do it on-the-fly.

I don't want "mysqldump > /dev/tape" because there is no metainfo and no way to know the tape has any content/

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by (71.8m points)

User parkydr gave the better answer:

You can't create a tar file from stdin. Each file in the tar has a header including the length of the file, so tar has to know how much data there is before writing the header. – parkydr


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