Re: [Gnu-arch-users] tar for the base revision

[David Brown]

On Tue, Sep 23, 2003 at 04:35:04PM -0700, Tom Lord wrote:

>     > How is cpio by these measures?  
> 
> I forget.  I explicitly rejected it for some reason.  And I don't
> really have enough desk-space here to maintain a proper labnotes
> workbook --- so I forget exactly why I rejected it.   But I do
> remember explicitly considering it.

The primary complaint against cpio is that it only stores numeric
uid/gid fields.  I would guess that arch would always want to extract
using the current user's id anyway.

Some additional problems, that may not be major:

  - There are a few variants of the format.  But, a few are portable
    (use ASCII characters for the fields).

  - The user interface is quite arcane.  It requires on stdin a list of
    the files/directories to archive.

  - You can't store a file named !!!TRAILER

  - The format only stores 16 or 32 bits of inode information.  This
    only affects hardlinked files, and most implementations successfully
    work around this.

  - _Most_ implementations, other than Gnu cpio have a bunch of strange
    bugs, usually resulting in files not getting backed up.

The last one would certainly be a winner.

Although, the file format is simple enough that for arch purposes, the
code to build and expand the archives could be added to arch fairly
easily.

Dave