Where do I find my mac that is connected via Firewire in Terminal application?

I have my iMac and MB pro connected by firewire. I can see the connection in the finderwindow, but can't locate the machines in terminal. Can someone help me? I do most of my work in Terminal and would like to move/copy files from one machine to another like that -- I could have sworn I was able to do it before with my MB Pro and my other iMac. Please help! I think I'm maybe not setting something I should be.

Also, it seems that whenever I connect to my firewire machine from the finder window (using 'connect as' and typing in the username and password,) I lose the connection when I switch to another window and I'm back to being connected as a 'guest', What's going on and how do I maintain that connection?

It may be acting like a network connection, not a mounted filesystem.

So how do I know which connection I have, and how do I only make it I firewire connection? Is the network connection something that happens automatically when you have the computers going through the router?

And what exactly is a mounted file system?

I'm trying to give you whatever clues I can to help you find the answer but don't know it myself. I'm not intimately familiar with how the connection between macs works. But I do know a tiny bit about firewire, including that it acts like a network connection when you plug it between computers.

A mounted file system is a file system you see in the shell like /path/to/files. To access the remote files you'll need to mount them somehow.

[edit] goggling "apple file sharing" showed me that OSX may be using AFP (apple filing protocol) for this. There are ways to mount AFP from the shell. See here

boot one in FW target disk mode. Go to System Preferences, start up disk, and click on target disk mode. This will cause one Mac to boot into FW Target Disk mode, which will then allow it to be mounted like if it were an external HD.