From: Keith Thompson on
John Kelly <jak(a)isp2dial.com> writes:
> On Tue, 15 Jun 2010 18:04:03 +0200, Tuxedo <tuxedo(a)mailinator.com>
> wrote:
>
>>I did 'man dd' but remain somewhat puzzled... I'm not familiar with the
>>command line options. I know I'm asking free advise here, but how would you
>>divide a file named for example myBigCrapBox into ten pieces using dd ?
>
> "count" limits the number of blocks copied
>
> "seek" determines the starting block
>
> "bs" sets the block size, for example bs=4k
>
> "if" is your input file
>
> "of" is your output file (creates if not existing)
>
>
> Experiment with some junk file till you get the hang of it. But be
> careful, you can really hurt yourself with dd while logged in as root.

As someone else mentioned downthread, "split" is probably better
than "dd" for this purpose. "csplit" may be even better (I've
never used it myself).

As for using it while logged in as root, you shouldn't even *consider*
doing something like this as root. Non-root accounts exist for a reason.

--
Keith Thompson (The_Other_Keith) kst-u(a)mib.org <http://www.ghoti.net/~kst>
Nokia
"We must do something. This is something. Therefore, we must do this."
-- Antony Jay and Jonathan Lynn, "Yes Minister"
From: Tuxedo on
Tuxedo wrote:

[...]

> So it just returns 'data'. I guess it is 'compacted' Mozilla mailbox data.
> I'm searching various Mozilla related sites for possible solutions. At the
> same time I have a feeling even if there is some way to 'uncompact' the
> data my system will likely run out of memory while trying to do so. I
> guess I could split the file first with dd, but then it might not work to
> uncompact properly.

Although this information is largely irrelevant to comp.unix.shell, I found
that the Mozilla mbox 'compact' is not a compressed format after all, but
simply plain text:
http://forums.mozillazine.org/viewtopic.php?p=9510377#p9510377
http://kb.mozillazine.org/Compacting_folders#What_is_compacting.3F

It appears I have a seriously broken mbox which is surely beyond any means
of repair. I presume the mail application must have been trying to write to
file by compacting/deleting or perhaps appending new messages while the
system or simply the application must have crashed (as suggested by
Christian Brabandt in a post) and that it resulted in 2.8GB of gibberish
being written to the file. It's the only logical conclusion I can imagine.

Thanks to everyone for their response in trying to solve the unsolvable....

Tuxedo
From: Rikishi42 on
On 2010-06-18, Tuxedo <tuxedo(a)mailinator.com> wrote:
> It appears I have a seriously broken mbox which is surely beyond any means
> of repair. I presume the mail application must have been trying to write to
> file by compacting/deleting or perhaps appending new messages while the
> system or simply the application must have crashed (as suggested by
> Christian Brabandt in a post) and that it resulted in 2.8GB of gibberish
> being written to the file. It's the only logical conclusion I can imagine.
>
> Thanks to everyone for their response in trying to solve the unsolvable....
>
> Tuxedo

ALl right allready. Just put the file up for download somewhere, we'll have
a look at it. :-)


PS: don't forget to compress it.

--
Any time things appear to be going better, you have overlooked
something.