Re: Tramp: hangs with “found remote shell prompt”, got `run nil “/bin:/usr/bin”` repeatedly in debug buffer

[Wenguang Wang]

> Btw, which shell do you run remotely? zsh?

I use bash at /bin/bash

> emacs -Q --eval '(tramp-verbose 10)'

I got this error:

eval: Symbol’s function definition is void: tramp-verbose

So I tried:

emacs -Q --eval '(setq tramp-verbose 10)’

And tramp worked!

So it has to be a problem in my .emacs. I will bisect and find out.

Thanks!
-Wenguang

> On Apr 9, 2020, at 2:27 AM, Michael Albinus <address@hidden> wrote:
> 
> Wenguang Wang <address@hidden> writes:
> 
>> Michael,
> 
> Hi,
> 
>> I hope the error message is not "found remote shell prompt” when it
>> cannot find the shell prompt :)
>> 
>> So I added the following line in the “~/.profile” of the Linux box:
>> 
>> [[ $TERM == "dumb" ]] && PS1='$ ' && return
> 
> That looks good.
> 
>> This changed the shell prompt to “$ “. Then I ran the following
>> command:
>> 
>> (setq tramp-shell-prompt-pattern "^[^>$][>$] *")
> 
> This shouldn't be necessary. There's always a chance that some hidden
> escape sequences are transferred. Tramp tries to handle them.
> 
> Btw, which shell do you run remotely? zsh?
> 
>> Now my tramp session hang on a slightly different error message: Found
>> remote shell prompt on ‘homes.local’
>> 
>> And the full trace file is below:
>> 19:09:20.311865 tramp-send-command (6) # exec ssh -l local  -o 
>> ControlMaster=auto -o ControlPath='tramp.%C' -o ControlPersist=no -e none 
>> homes.local
>> 19:09:21.224814 tramp-process-actions (6) # 
>> Welcome to Ubuntu 18.04.4 LTS (GNU/Linux 4.15.0-76-generic x86_64)
>> 
>> * Documentation:  https://help.ubuntu.com
>> * Management:     https://landscape.canonical.com
>> * Support:        https://ubuntu.com/advantage
>> 
>> * Kubernetes 1.18 GA is now available! See https://microk8s.io for
>> docs or
>>   install it with:
>> 
>>     sudo snap install microk8s --channel=1.18 --classic
>> 
>> * Multipass 1.1 adds proxy support for developers behind enterprise
>>   firewalls. Rapid prototyping for cloud operations just got easier.
>> 
>>     https://multipass.run/
>> 
>> * Canonical Livepatch is available for installation.
>>   - Reduce system reboots and improve kernel security. Activate at:
>>     https://ubuntu.com/livepatch
>> 
>> 5 packages can be updated.
>> 4 updates are security updates.
>> 
>> *** System restart required ***
>> Last login: Tue Apr  7 19:08:40 2020 from
>> fe80::1c74:9720:e127:bea4%wlp2s0
>> $ 
>> 19:09:21.224922 tramp-get-connection-property (7) # process-buffer nil
>> 19:09:21.225137 tramp-process-actions (3) # Waiting for prompts from
>> remote shell...done
>> 19:09:21.225319 tramp-maybe-open-connection (3) # Found remote shell
>> prompt on ‘homes.local’
> 
> This is the message about "Found remote shell prompt". And this is true, 
> indeed.
> 
>> 19:09:21.227484 tramp-send-command (6) # echo \"`getconf PATH 2>/dev/null`\" 
>> 2>/dev/null; echo tramp_exit_status $?
>> 19:09:24.258471 tramp-accept-process-output (10) # *tramp/ssh 
>> local@homes.local* run nil
>> "/bin:/usr/bin"
>> tramp_exit_status 0
>> $ 
> 
> And here Tramp hangs. Hmm, it shouldn't.
> 
> Could you pls repeat the test, w/o changing tramp-shell-prompt-pattern?
> Best would be to run
> 
> emacs -Q --eval '(tramp-verbose 10)'
> 
> and then open the remote file.
> 
> Best regards, Michael.