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Re: Hangs on password queries once SSH session is up

(resending, I didn't see it appear in the archive after a day)

> > Are these linux commands (ftp, sudo, &c) using the SSH authentication
> > mechanisms again?
> No, they're basically standard applications using the console to
> read/write characters on stdout/stdin.

As I thought. This makes the problem even more intriguing.

> So if I understand, your problem is that channel_poll is blocking. This
> is indeed a problem and should not happen. In order to help us find out
> what happens, could you:

Yes, it blocks in these scenarios, but not otherwise (I now use the
SSH client all day long, and it works fine). And if I provide the
ftp password thru .netrc on the remote system, no issue either. So
it really seems to be related to echo control (or some other pty

Yet on most systems, "stty -echo" works as expected, so it's not
echo control per se (and editors also turn that off).

Again, I don't think it's a problem with the library, more likely
with the way I'm using it.

> -tell which version of libssh you're using (master from git, release, ...)

libssh-0.4.2 (sources from http://www.libssh.org). Not sure
about the "master from git", will try to figure it out.

> -call the ssh_options_set() function with the verbosity level set to the
> highest level (which dumps a call trace) and attach the output in your mail

It may be a little while before I have time do this, as I'm not
sure where the call trace goes just now. But I will as soon as I

> -compiling your application with full debugging symbols, running your
> program in gdb, then ^C it when the problem happens, then dump a C/P of
> the result of the following command:
> bt

Not sure what C/P stands for, but the call chain I provided in the
original post was meant to be equivalent to a bt under gdb. It comes
by mapping the addresses in the ltcSSH.exe.stackdump file that is
produced on killing the client with the symbols in the link map.

I will have to try running under gdb, should be interesting.

Also, C-C does not work to stop the client, as that is simply passed
to the remote host. So I get the pid of the process (since, for now,
it's compiled in a cygwin environment) and can then send it a signal.
Works fine too.


Re: Hangs on password queries once SSH session is upAndreas Schneider <asn@xxxxxxxxxxxx>
Re: Hangs on password queries once SSH session is upAris Adamantiadis <aris@xxxxxxxxxxxx>
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