Re: M-x shell fails in tramp buffer

[Michael Albinus <michael.albinus@gmx.de>]

"Chris Moore" <dooglus@gmail.com> writes:

> Visit some FTP site:
>
>   "C-x d /anonymous@ftp.gnu.org:/ RET"
>
> Then try running a shell:
>
>   "M-x shell RET"
>
> I see a backtrace:
>
> Debugger entered--Lisp error: (wrong-type-argument processp nil)
>   process-coding-system(nil)
>   comint-exec-1("shell" #<buffer *shell*> "/bin/bash" ("--noediting" "-i"))

comint-exec-1 uses start-file-process now, which starts a process
depending on the file name handler responsible for default-directory.
ange-ftp is not able to start a process; it always returns nil for
start-file-process.

I've added a check in comint-exec-1 to raise an error if
start-file-process returns nil. Additionally, if you start "shell"
with a prefix argument, and default-directory is a remote file name,
you will be prompted now to change the value of default-directory.

  "C-u M-x shell RET"

shall be reasonable now if you are on a remote FTP site.

Best regards, Michael.