UNIX for Dummies Questions & Answers

Hi all,

I have a tar file that was done with tar -cvf <tar_file> /directory.

Is there any way that I can untar this, i.e. tar -xvf <tar_file> into a different directory?

So far Google said you can't do tar -xvf to a different directory.

Unfortunately, am not the one doing the tar -cvf and I cannot convince the third-party to change their scripts as this is the syntax in all of their scripts.

Any advise of any workaround will be very much appreciated. Thanks in advance.

Maybe you are looking for this?

Code:

tar cvf - cur_directory  | (cd newdirectory &&  tar xvf -)

Bad news...
The standard behaviour of tar, if not given a relative path when creating an archive (that is ./ ) will always use an absolute path. But I never tried to see what happens with a chroot... (man chroot ! )

chroot will do it but requires some configuration to work. Alternatively, you might use gnu tar which removes the leading slash by default, unless the -P option is given.

If Gnu tar isn't installed, you can still use pax which handles tar files and has an option to replace on the fly the path of extracted files. (eg: pax -s /directory/newdirectory/ ... ).

I think you have justifiable cause to ask the third party to use relative paths when creating an archive with "tar".

jlliagre's idea of using "pax" is good. It has saved me much time before.

What Operating System and version are you using to read the "tar" archives. Do you have pax"?

As I am sure you know, "tar -tvf" will list the filenames on the archive enabling you to check whether you have a clash with your system. We don't know the structure of your filesystems in relation to the directory structure of the "tar" archive or whether this involves active files or programs.

Personally if I had to deal with unsolicited "tar" archives I would use an intermediate computer to inpect, expand (with "pax" to a controlled filesystem), check for viruses, perform basic data validation, and then transfer to the main computer for processing.

Hi Dennis,

Unfortunately, am tarring xvf from a file

---------- Post updated at 07:12 PM ---------- Previous update was at 07:09 PM ----------


Hi metyhl,

Am on AIX, did a which and there is /usr/bin/pax

I'll check on the man pages and see how it works, never used it before. As per jlliagre's post, I can use pax to extract from tar files as well, is that correct?

Yes, pax can extracts tar files. It uses that file format by default actually.