Re: tramp (2.1.16-pre); Documentation for tramp-encoding-shell unclear

[Michael Albinus]

David Abrahams <address@hidden> writes:

Hi David,

this is an answer to an older mail from you; I'm cleaning my
not-yet-answered-issues-stack ...

> The documentation for tramp-encoding-shell states:
>
>   *Use this program for encoding and decoding commands on the local host.
>   This shell is used to execute the encoding and decoding command on the
>   local host, so if you want to use `~' in those commands, you should
>   choose a shell here which groks tilde expansion.  `/bin/sh' normally
>   does not understand tilde expansion.
>
>   For encoding and deocding, commands like the following are executed:
>
>       /bin/sh -c COMMAND < INPUT > OUTPUT
>
>   This variable can be used to change the "/bin/sh" part.  See the
>   variable `tramp-encoding-command-switch' for the "-c" part.
>
>   Note that this variable is not used for remote commands.  There are
>   mechanisms in tramp.el which automatically determine the right shell to
>   use for the remote host.
>
> So if it's not used for remote commands, what /is/ it used for?  I would
> like an example, please, because "the encoding and decoding command on
> the local host" is still to vague to me.  It's hard to decide "if I want
> to use `~' in those commands" without being able to tell which "those
> commands" are.

The documentaion is related to *inline* methods, like ssh. If you want
to copy a file from a remote machine to a local machine, Tramp encodes
the file on the remote machine with base64 or uuencode; the (ASCII)
output of this encoding goes to an Emacs buffer.

Afterwards, a process on the local machine is started, with
`tramp-encoding-shell' as the surrounding shell. This process gets the
above buffer as input, and decodes it to the resulting file with the
opposite command.

> Thanks

Best regards, Michael.