Fwd: Re: Unusual Question

Matthias Apitz guru at unixarea.de
Mon Jul 10 20:18:47 UTC 2017

El día lunes, julio 10, 2017 a las 03:16:31p. m. -0400, Mike Jeays escribió:

> On 17-07-10 01:38 PM, Polytropon wrote:
> > On Mon, 10 Jul 2017 17:36:19 +0200, Matthias Apitz wrote:
> >> The OP should just compile an own version of dd(1) which punches lets say
> >> every thousand blocks the current block number to see how far (or better
> >> how less) it will walk through before the kernel halts/crashes.
> > To extend this idea:
> >
> > I'd add a few continuous diagnostic messages (comparable to
> > the ^T status display), so when the SSH connection finally
> > drops, it's possible to see how far the dd process went. :-)
> dd can be made to report its status by sending the kill command USR1.
> See man dd. You could send one every minute via cron.

You can assume that I do know dd(1) and its man page. I just do not think
that it will work on a system and kernel being overwritten with zeros,
running somethings like cron jobs (as you suggest) or shell loops of
sleep and kill pid. Adding a fprintf(stderr, ....) to the source of dd
is better, don't you think so?


Matthias Apitz, ✉ guru at unixarea.de, ⌂ http://www.unixarea.de/  ☎ +49-176-38902045
Public GnuPG key: http://www.unixarea.de/key.pub
8. Mai 1945: Wer nicht feiert hat den Krieg verloren.
8 de mayo de 1945: Quien no festeja perdió la Guerra.
May 8, 1945: Who does not celebrate lost the War.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: not available
URL: <http://lists.freebsd.org/pipermail/freebsd-questions/attachments/20170710/9ee77347/attachment.sig>

More information about the freebsd-questions mailing list