Re: [Dar-support] backing up directly to tape

[Gour <go...@at...>]

Denis Corbin <dar...@fr...> writes:

> piping one command's output to a pipe is for the whole life of that
> program, this is the shell that binds the stdout to something like a
> special device inode or a plain file or an anonymous pipe, for example.

OK, this is, I assume, clear to me.

> Good question! Well this is something that is missing to dar, at first
> I thought outputing dar to the split command would have solve the
> issue but nop, split does not help sending again data to a
> file/special device once end of file was met.

It means one is, in general, supposed to create all the slices with dar
and then send them to 'remote' devices for storage?

> I think about adding a dar independent program for now (let's call it
> dar_split) that would copy its stdin to its stdout and suspend when it
> reached end of file (on output), having the user able to change the
> tape and let the output continue on a new tape. A program that could
> also work the other direction, by gathering different tapes in input
> also suspending when reaching eof of file (on input) and outputting to
> stdout. So piping dar output to dar_split should probably address your
> need and reading dar in sequential-read mode from dar_split would let
> you access your archive without having to copy from tape to disk first.

It sounds good.

> This type of program seems feasable and quit simple, see attachment, I
> have not tested it much but it seems to work as expected.

Thanks a lot - I'll try it out.

> In consequence, if dar archive are not larger than one tape you don't
> need anything more than dar, else you would require dar_split piped to
> the dar output or to dar input (with dar used in --sequential-read),
> The good point too is that you don't have to calculate the size of
> slices to use:

That's cool!!

> If that matches your need I will integrate that program (after more
> intensive testing) into dar for next major release.

Thanks a lot...however, if next major dar relase won't be very soon, I
believe we'll migrate to RDX in between. ,)


Sincerely,
Gour

-- 
Even a man of knowledge acts according to his own nature, for 
everyone follows the nature he has acquired from the three modes. 
What can repression accomplish?