Re: tar/cpio data read from pipe?

>>>>> "Dan" == Daniel Zepeda <zepeda_at_am51.wg.waii.com> writes:
 

>>>>> "Dave" == Dave Plonka <dev_dp_at_mfa.com> writes:

    Dave> Can be mapped to the use of either tar or cpio? Both of     Dave> these seem to require a filenames...

    Dan> tar and cpio definitely don't need filenames. I believe that
    Dan> cpio's default input is standard input, tar can take standard
    Dan> input by specifiy "-" as the filename argument.

They both do need filenames to create archives. Cpio can accept a list of filenames from stdin. Consider that what is going into the archive is the contents of each file preceded by directory info. A pipe fed into tar/cpio cannot provide the latter. A fifo might be able to provide a name but no size.

There does seem to be a gap in the standard tools. Cpio and tar can write to multiple tape volumes but their backends are not accessible. Dd is not really up to tape changes, especially with variable tape capacity. Perhaps GNU has something. You may at least be able to merge parts of dd, cpio or tar to do what you want.

-- 
Pete Forman
Western Geophysical
pete.forman_at_bedford.waii.com