Run Remote ssh command with Full Login Shell

Question

I would like to do something like ssh example.com 'ls' However per ssh manpage:

If command is specified, it is executed on the remote host instead of a login shell.

So what happens is that ls displays its output and then ssh exits.

What I can't figure out is how to have the full login shell open and then have the command run inside that shell. Leaving the shell open after the command is run. As if I had manually done the following:

  localhost$ ssh example.com 
example.com$ ls
             /folder1 
             /folder2 
example.com$ _

Any ideas?

Answer 1

Just tell bash to execute ls and then itself in a login shell

$ ssh user@host  -t 'bash -l -c "ls;bash"'

Answer 2

ssh user@host -t 'ls; exec $SHELL -l'

-t Force pseudo-terminal allocation. This can be used to execute arbitrary screen-based programs on a remote machine. Is slightly more proper than bash -i.

exec No new process is created.

-l looks for ~/.bash_profile, ~/.bash_login, and ~/.profile, in that order, and reads and executes commands from ... Without this you probably can not run scripts/commands from ~/bin directory, because this code from ~/.profile will not be executed without -l flag:

if [ -d "$HOME/bin" ] ; then
    PATH="$HOME/bin:$PATH"
fi

Answer 3

In your comment on fons's answer, you say that it doesn't work while using screen.

Could you elaborate on that? Looking at the source code for openssh, sshd executes the command by calling

YOUR_DEFAULT_SHELL -c COMMAND

So, for example, if your default shell is screen, then this won't work all that well because screen's -c flag just overrides its .scrreenrc. So, there's really no way to send commands to screen if it's your default shell. You'll have to actually run screen as the command given to ssh, but with a default shell that isn't screen.

If that's what you're trying to do, I think things will get really weird, since screen will also close windows with non-interactive programs, so you'll have to do a similar trick to fons's, but one level deeper. SO, with, e.g. /bin/bash (and not screen) as your default shell Something like:

ssh user@host -t 'screen bash -l -c "ls;bash"'

Which should --take a deep breath-- ssh into the host, run bash -c with a command of screen, which will make a new window. If this window just opened up ls, it would end, and screen would terminate, so we use fons's trick inside the new screen window.

I think that'll work, if that's even what you were trying to do ;)

Answer 4

I use Windows and maybe because of this, the -t flag does not work for me.

To execute the ssh command with logging, I first call the files /etc/profile and ~/.profile.

In totoal, my command has the form:

ssh [email protected] 'source /etc/profile; source ~/.profile; my bash code'

Answer 5

Because I often struggle with properly escaping my command, grab this function:

sshlogin() { ssh -tt "$1" "$(printf "%q " bash -lc '"$@"' -- "${@:2}")"; };

with it not only login shell is run, but also spaces and quoting are preserved:

$ sshlogin server echo "a    space    b"
a    space    b

Answer 6

I found this thread while looking for a way to run a python command, within a miniconda environment, on a remote host.

The solution which worked for me was like this:

ssh user@host -t 'bash -i -c "<conda-command>; cd <dir>; python <script.py> <arguments>"'

Note the command passed by SSH (within the outer single quotes) is to run bash -i -c, with everything in the "", which are within the '' pair, then being the commands which that bash shell runs. Note this means any double-quoted options passed to the python script then needs to be escaped with a backslash, so --option \"cute fluffy kittens\".

This didn't work for me using bash -l, but I saw the reference to bash -i in one of the answers above, tried it, and it worked.

Answer 7

Multiple -t options force tty allocation, even if ssh has no local tty:

ssh -tt user@host 'bash -l -c "/path/to/command'