What does `tar -C` mean?

In the section "Installing Portage", the Gentoo installation docs say:

# tar xvjf /mnt/gentoo/portage-latest.tar.bz2 -C /mnt/gentoo/usr

What does this command do?

guilin 桂林

Posted 2011-12-02T10:17:07.867

Reputation: 311

Answers

Tar is used to handle archives (historically saved on tapes).

The x tells it to extract files from the archive
v stands for verbose
j for bzip2 archive
f indicates the file name
finally: C tells it to change directory (so the package content will be unpacked there)

See also man tar.

choroba

Posted 2011-12-02T10:17:07.867

Reputation: 14 741

I've also seen -C used while creating an archive. What does it mean in that context? – frakman1 – 2020-01-23T21:51:21.217

@frakman1: Do I really have to copy the contents of man tar here? – choroba – 2020-01-23T22:11:53.247

The man page just says change to directory DIR which is not very helpful. Saying "(so the package content will be unpacked there)" on the other hand, is. – frakman1 – 2020-01-23T22:19:13.317

OK. When -C is used while creating an archive, it specifies where to search for the files to archive. – choroba – 2020-01-24T09:58:02.570

If you ever need to know what a parameter does again, try to read the man first. The command man tar, and then doing /-C will get you to the section describing what -C stands for, which in this example represents 'change directory' (i.e. sends the results of the unpacking to /mnt/gentoo/usr).

timss

Posted 2011-12-02T10:17:07.867

Reputation: 369

It unpacks /mnt/gentoo/portage-latest.tar.bz2 in /mnt/gentoo/usr/

Tog

Posted 2011-12-02T10:17:07.867

Reputation: 4 747