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

 
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# 1  
Old 03-09-2011
Difference between 'pax', 'tar', and cpio
Could any one please help me in understanding the difference between pax,tar and cpio. all of them basically creates archive files.
# 2  
Old 03-09-2011
cpio is more advanced than tar, in a way that it can preserve file ownership, permissions and even timestamps. But it is also not so easy to use. I don't know much about pax. From what I remember it can convert between some archive formats or something Smilie
# 3  
Old 03-09-2011
Hi.

See http://en.wikipedia.org/wiki/List_of_archive_formats

Google, Wikipedia and man pages are your friends for factual information ... cheers, drl
Last edited by drl; 03-09-2011 at 11:12 AM..
# 4  
Old 03-09-2011
Quote:
Originally Posted by bartus11
cpio is more advanced than tar
cpio has many limitations and so does tar.
Quote:
in a way that it can preserve file ownership, permissions and even timestamps.
"tar" hopefully does that too.
# 5  
Old 03-09-2011
Quote:
Originally Posted by bartus11
cpio is more advanced than tar
The cpio utility is depreciated circa POSIX 2001 because it can't hold files >8GB.
Quote:
it can preserve file ownership, permissions and even timestamps.
So does any sensible UNIX archiver. tar does this by default. It was kept and extended to allow >8GB files while keeping backwards compatibiltiy with old tar: files < 8GB still use octal fields, but files >8GB use binary fields in such a way that archivers who don't understand those fields will ignore them.

The new pax format is in fact an extension of this extended tar, with a huge default blocksize and one optional extra field to carry filenames, group ID's, etc. that can't fit inside a normal tar's fields(groupid's > 07777777, etc.)
Last edited by Corona688; 03-09-2011 at 12:01 PM..
# 6  
Old 03-09-2011
Sorry guys, little brain freeze or something, I mixed "tar" with "cp" Smilie
# 7  
Old 03-09-2011
Standard "cpio", "tar" and "pax" have a 2Gb maximum size of any one file. There may be enhanced versions but don't assume cross-platform compatibility.
 
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