mrktools

A command line tool for performing some simple tasks with the Remarkable device that the desktop app doesn't do for me.

Overview

The Remarkable device is a linux box, and it's running an ssh server. This means that we can use 'ssh' and 'sshfs' to manipulate the device state and the files which are installed on it.

mrktools assumes that:

ssh is available in the PATH. Ideally, you have set up a public key on the device so that a password isn't necessary, but a password prompt will work if necessary.
sshfs is available in the PATH. See the comments under ssh.

Usage

Documentation gets stale. Please check mrktools --help for the most up-to-date usage information.

Since everything is done over a ssh tunnel, the host param is almost always required.

--host - the IP address or hostname of the Remarkable device.
--user - the username of the root user on the device. Defaults to root and there is probably no reason to change it
--mount_point - a non-existing directory to use as a mount point for sshfs. Defaults to ./rem.

Subcommands

restart - will restart the xochitl process on the device. Changes to the files in the data directory will not be noticed, so a restart is often desired.
ls - list all of the files in the xochitl data directory. This is a recursive listing. I only really found it useful for debugging, but maybe it has other uses.
copy - recursively copy a directory to the data directory on the device with an optional restart.
ipdf - convert images into pdf files. Optionally, convert them to something that looks better on the device. Also optionally, copy them to the device and/or restart the xochitl process.

Examples

mrktools --host remarkable.mynet ipdf -b -p 'Parent' -c -r -a 25 *.jpg

Copies all jpegs in the current directory to the Remarkable under the 'Parent' folder. Those files will be converted to dithered black-and-white with a pre-multiplied alpha value of 25%.

mrktools --host remarkable.mynet restart

Restart the xochitl server on the device. Note that this does not restart the actual device.

Warnings

sshfs runs a fairly fragile service on a low-level of the kernel stack. When it fails, you may need to restart your entire device. At the very least, you will get non-killable zombies that will slow everything down.

I suggest opening the device and ensuring that it is active before running mrktools to avoid any problems. mrktools tries to be very clean about starting and stopping the sshfs service when it runs, but if it fails to shutdown cleanly, bad stuff can happen. Not ideal, but it was the most direct route to the functionality I desired.

To Do

At this point, this meets my needs, but it's a fun little project (when it's not locking up my computer), so I may make some tweaks. Specific things on my radar:

Only mounting sshfs when required. Currently, it mounts immediately which can cause delays and unnecessary fragility - especially for operations like restart which don't require any access to the filesystem.
Adding a environment variable for the host, allowing running mrktools without putting the --host param in there every time. The only reason that I haven't done this yet is a) I have hard-coded the value for my home network, and b) the value will change as you move networks, so it's of limited utility on a laptop that you carry around.

Resources

These operations were cribbed largely from these sources:

Software for the reMarkable tablet - Prof. Eric Fraga's notes on a similar project. In his case, he is manipulating PDFs whereas I wanted to install images on the device that don't look like crap. (And that have thumbnails. Just copying a PDF to the device will often not get a thumb.)
Filesystem Layout - from the reMarkableWiki. This is an invaluable resource for anyone doing anything with the reMarkable.

gmadrid / mrktools