A long time ago I happened to come across a few STC MCU's and wrote stcdude. At that time there were no linux soutions for the problem. It was hacky as hell in places, but got the job done for me.
Time went on, I had literary no time to work on STCDUDE, and most of my projects used other mcus. Right now, there's a better and more clean solution (that I was not aware of for a while): stcgal
https://github.com/grigorig/stcgal
It packs way more features and, let's be honest, @grigorig had way more time to work on it and it fully supports STC89 that I had literary no time to implement in stcdude.
The code will still be here for historical purposes and since links from hackaday will land you on this very page, so if you want - you may give it a try.