VC via tramp without vcdiff

VC via tramp without vcdiff

[Yary Hluchan]

I'm editing files under revision control (plain SCCS) on a remote
host, using tramp. The remote host doesn't have an implementation of
vcdiff, nor does it have any c-compiler with which I can build an open-
source vcdiff implementation. Emacs wants to run vcdiff with every
check-in and when that fails, VC fails.

Can I tell Emacs/tramp to use "sccs diffs" instead of "vcdiff" for
sccs (or even for everything)?

Even if I could find a perl vcdiff or a pre-compiled vcdiff, I'm not
sure I have permission to put it in a place where emacs could find it
on that system, or how to tell tramp to add to its $PATH.

Re: VC via tramp without vcdiff

[Michael Albinus]

Yary Hluchan <yary.hluchan@gmail.com> writes:

> I'm editing files under revision control (plain SCCS) on a remote
> host, using tramp. The remote host doesn't have an implementation of
> vcdiff, nor does it have any c-compiler with which I can build an open-
> source vcdiff implementation. Emacs wants to run vcdiff with every
> check-in and when that fails, VC fails.

vcdiff is a shell script, which comes with Emacs. So you can copy your
local version to the remote host, let's say into your home
directory. Don't forget to set executable permissions.

> Can I tell Emacs/tramp to use "sccs diffs" instead of "vcdiff" for
> sccs (or even for everything)?

The call of vcdiff is hard-coded in `vc-sccs-workfile-unchanged-p' and
`vc-sccs-diff'. I wouldn't change that.

> Even if I could find a perl vcdiff or a pre-compiled vcdiff, I'm not
> sure I have permission to put it in a place where emacs could find it
> on that system, or how to tell tramp to add to its $PATH.

Assumed you run Tramp 2.1 (part of Emacs 23.1), you can extend the
remote $PATH to look in your home directory:

  (add-to-list 'tramp-remote-path "/my/home/directory")

Best regards, Michael.