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Difference between 'pax', 'tar', and cpio

 
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# 8  
Old 03-10-2011
Quote:
Originally Posted by methyl
Standard "cpio", "tar" and "pax" have a 2Gb maximum size of any one file.
standard "tar" has a much bigger limit now, but old versions persist in many places.

Of course PAX supports large files. It's not a modern restandardization of something old, it's a brand-new archiver invented by IEEE&POSIX and decreed by POSIX to support all the modern extensions for tar as well as it's own pax format. I suspect because they'd have to pry some distributor's mouldy old tar implementations from their cold dead fingers to get USTAR implemented anywhere else.

Of course, it being an actually portable archiver, nobody installs it Smilie
Last edited by Corona688; 03-10-2011 at 12:23 PM..
# 9  
Old 03-10-2011
Hi.

I just noticed that one of the archivers available in GNU/Linux Debian (lenny) is:
Code:
Description: tar(1) from FreeBSD, using libarchive
 The bsdtar program has a number of advantages over previous tar
 implementations:
 .
  * Library. Since the core functionality is in a library, it can be
    used by other tools, such as pkg_add.
 .
  * Automatic format detection. Libarchive automatically detects the
    compression (none/gzip/bzip2) and format (old tar, ustar, gnutar,
    pax, cpio, iso9660, zip) when reading archives. It does this for
    any data source.
 .
  * Pax Interchange Format Support. This is a POSIX/SUSv3 extension to
    the old "ustar" tar format that adds arbitrary extended attributes
    to each entry. Does everything that GNU tar format does, only
    better.
 .
  * Handles file flags, ACLs, arbitrary pathnames, etc. Pax interchange
    format supports key/value attributes using an easily-extensible
    technique. Arbitrary pathnames, group names, user names, file sizes
    are part of the POSIX standard; libarchive extends this with
    support for file flags, ACLs, and arbitrary device numbers.

Looks like a super-set of even PAX. Nothing is mentioned explicitly about sizes handled, and I have been able to get by with GNUtar, so I have no direct experience with bsdtar ... cheers, drl
# 10  
Old 03-15-2011
tar is the best choice as it works well for the purpose. The cpio has some advantages when compared to tar , but it is quite complicated to control the use. The pax is not interesting one for me though it implements least privilege protections for memory pages and i have well experience with tar. One of the essay writing service attempt based on this items cleared some benefits of tar that actually works greatly for me. The selection also depends on several tasks that each one needs to accomplish.
 
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