Re: background processes?

From: Nico Kadel-Garcia (nkadel@bellatlantic.net)
Date: 09/25/02 

From: "Nico Kadel-Garcia" <nkadel@bellatlantic.net>
Date: Wed, 25 Sep 2002 13:03:58 GMT

"Dimitri Maziuk" <dima@127.0.0.1> wrote in message
news:slrnap1cf0.k9k.dima@odyssey.bmrb.wisc.edu...
> thus spake Richard Silverman:
> >>>>>> "JM" == Joe Mildenberger <Joe.Mildenberger@triumf.ca> writes:
> >
> > JM> I'm not arguing with the presumed reason for having this
> > JM> annoying (yes, it _is_ annoying!) feature
> >
> > There is nothing "presumed" about it; the problem is there.
> >
> > JM> but it seems to me to be more in the realm of programming
> > JM> "busybody-ism" than in something that would genuinely help me in
> > JM> doing my job.
> >
> > Did you actually read the link I posted? The problem, unaddressed,
causes
> > random unpredictable data loss. That's generally considered a bad
thing.
> > For instance, the reported symptom which caused this problem to be
> > discovered and addressed, was that every once in a while, scp would
> > corrupt files it transferred.
>
> There is a reason why ftp uses 2 ports and 2 protocols: one for
> interactive command session, and one for data transfer. SSH author,
> presumably, flunked his Networking 101, otherwise he would've known
> what that reason is.

And forwarding ftp is thus one of the hairiest pains known. Not appropriate
for SSH!

> > JM> I mean, really, how is it helping me by producing these hung
> > JM> sessions?
> >
> > It is not "producing these hung sessions." *You* are producing them, by
> > starting processes on the server side which hold the input pipes to sshd
> > open. sshd has no way of knowing whether more data is coming or not, so
> > it does not exit. Close the useless file descriptors, and it will exit.
>
> This is getting silly. If run $FOO over RSH, there are no hung sessions.
> If I run the same $FOO over SSH, the session hangs. You're telling me
> I'm wrong to blame SSH for that? Puhleez...

SCP is doing a lot more and doing it more safely. Rsh did a *lot* of dumb
and dangerous things: should we implement those too, for convenience?

Just redirect your std* to /dev/null, and it should work.

Relevant Pages

  • Re: background processes?
    ... > JM> I'm not arguing with the presumed reason for having this ... If I run the same $FOO over SSH, the session hangs. ...
    (comp.security.ssh)
  • Re: background processes?
    ... DM> interactive command session, ... DM> would've known what that reason is. ... the immediate user process started by sshd; ... when do you terminate an SSH session? ...
    (comp.security.ssh)
  • Re: background processes?
    ... thus spake Nico Kadel-Garcia: ... >> interactive command session, ... SSH author, ... If run $FOO over RSH, ...
    (comp.security.ssh)
  • Re: RSH on SUSE Pro 9.1
    ... kenji.hirohama@gmail.com wrote: ... Any reason why you're using rsh and not ssh? ...
    (alt.os.linux.suse)
  • Re: How do you kill a completely locked up thread?
    ... In this particular case, I need SSH, which for some reason Microsoft doesn't ... back in the days where there was no memory protection for applications. ... rogue application could bring the entire system down. ...
    (microsoft.public.dotnet.languages.csharp)