$ scp (source path) (destination URI):(destination path)
For a stream between systems instead of a file, do it this way:
$ cat localfile | ssh user@host "cat > remotefile"
-- or --
$ ssh user@host "cat > remotefile" < localfile
e.g.
local$ ssh remote
remote$ # do some stuff
remote$ echo "Text" > file.txt
remote$ # oh, I need to copy file.txt back to my local host
remote$ #?If by "not externally accessible" you mean the local machine is not running an SSH server, but has an SSH client available and the machine is connected to the network, and the remote machine is running an SSH server, then:
$ scp remoteuser@remotehost:remotepath/remotefile localfile
Also, alternatively... pipe it to `mail` and send it over email.
local$ scp user@remote:/path/to/file.txt local_file.txt
local$ scp remote:~/file.txt ./