[darcs-users] [issue1371] darcs assumes -p for SSH_PORT; but putty takes -P

[Radoslav Dorcik]

On 05/29/2010 02:10 PM, Matthias Kilian wrote:
> Even worse: what if someone with a non-Windows operating system has
> some command named `plink' installed in his PATH, where that `plink'
> does something really evil[tm]?
>
> IMHO, this should be made configurable in some way (using the
> environment), but darcs should NOT run arbitrary commands at runtime
> to detect which implementation of ssh is installed.
>
>    

Exactly. Darcs should work only with its environment. Proposed 
auto-detection is not search for the right command in
user environment with guessing. Instead it recognizes provided command 
using "<cmd> -V" response.
But I'm not sure if this is something prohibited also. I can image that 
user has "ssh" command behaving on "ssh -V" like "rm -fr /etc/".

Darcs has already preferences file (global and repo related). If it is 
possible to enumerate all known ssh/sftp/scp usages in darcs
than the exposing configurable variables in form of command execution 
templates is other way to take.

Image something like:
ssh_cmd  = "@cmd@ -p @port@ @uri@ @remote_cmd@"
sftp_cmd = "@cmd@ -P @port@ @remote_uri@ @local_dir@"

It would make sense to think about the external command  access in 
broader sense (e.g. including diff).