This could actually be very useful!

I have some old DOS-based stock-taking software that has been working for years but needs to be ported to the web to remove the hassle of maintaining and updating it across old and new machines.

Porting it to something like this instead of reworking the interface completely could help speed up the process and users wouldn't be disturbed by the switch.

Sounds silly, but sometimes these old, primitive interfaces are all you need.

EDIT: anyone knows of other libraries that simulate terminals?

I'd look for a Javascript port of DOSBox.

A bit of googling brings up Emscripten DOSBox: https://github.com/dreamlayers/em-dosbox/

And JsDOSBox: http://sourceforge.net/projects/jsdosbox/

Related for the *nix folks: tty.js

https://github.com/chjj/tty.js

I don't really get why you need to render this on a canvas. It's text only, you should be able to render this in pure HTML with some CSS.

It's called hacking, scratching an itch to see what you can do using a different approach. Remember, this site is called "Hacker News".

I think it's pixel perfect this way.

Try 'format' ;-)