How to pass an environment variable through an ssh command?

command linessh

How can I pass a value into an ssh command, such that the environment that is started on the host machine starts with a certain environment variable set to my choosing?

EDIT:
The goal is to pass the current kde desktop ( from dcop kwin KWinInterface currentDesktop ) to the new shell created so that I can pass back an nfs locations to my JEdit instance on the original server which is unique for each KDE desktop. ( Using a mechanism like emacsserver/emacsclient)

The reason multiples ssh instances can be in flight at one time is because when I'm setting up my environment, I'm opening a bunch of different ssh instances to different machines.

Best Answer

The ~/.ssh/environment file can be used to set variables you want available for remote commands. You will have to enable PermitUserEnvironment in the sshd configuration.

Variables set this way are exported to child processes, so you can:

echo "Foo=Bar" > sshenv
echo "Joe=37" >> sshenv
scp sshenv user@server:~/.ssh/environment
ssh user@server myscript

and myscript will know that Foo is Bar and Joe is 37.