How can I transform a file on 1st machine with a tool on 2nd machine in one line over ssh?

Question

I have some file tools on a mint machine that I would rather not install on my mac laptop. Mainly because of the vastness of apt-get and the low risk of installation failure. Anyway, every so often I have a file that I want to process in place using some remote tool. Both machines can ssh right in to each other so I was figuring there must be some script or tool out there that would allow me to type out something like remote [file] [tool & args] to send my file to the other machine, get it processed, then get it back.

Answer 1

If the tool is a simple filter then you can just use it normally, but over ssh.

ssh user@host somefilter < infile > outfile

If it expects a filename but doesn't need to seek around in it or the output file then you can (ab)use bash for this.

ssh user@host bash -c "sometool <(/dev/stdin) -o >(/dev/stdout)" < infile > outfile

Otherwise you will have to transfer the file to or from the other system.

Answer 2

The UNIX concept is do one thing and do it quietly. You can then build your own tools based on those simple processes.

You just need to write a script which scp's the file to your machine, runs the ssh command to modify it and then pulls it back. Three lines, here's a very simple template,

scp oldfile myuser@myother.machine:/some/directory/file.to.process
ssh myuser@myother.machine "/usr/bin/something /some/directory/file.to.process"
scp myuser@myother.machine:/some/directory/file.which.is.processed newfile

Add parameters and put some error checking in and you're good to go.

Or, as the other answer shows, you can route stdin/stdout to the other machine so for filters, it's even simpler.

Answer 3

Well, you could set up X11 forwarding through ssh from the machine the file-to-process is located in. This page is a good tutorial on how to do this. It basically lets you run the program from the remote server on your computer (using your computer's resources).

Answer 4

You can also try mounting the other system as a directory. Then you can access it normally as if it was on your mint machine. sshfs is one way to do this.

mac$ ssh user@mint
mint$ mkdir ~/mac
mint$ sshfs user@mac:/path ~/mac
mint$ tool ~/mac/file