If you clicked the op link above, you may have noticed that it goes to a 404 page. (If you’re in the future maybe it works again; congratulations!) At least, as of December 2011, it is a 404 page and it’s been that way for at least a year now. The maintainer of the site (Alec Thomas) tells me that his server crashed some time back, and he hasn’t had the time to get all of the old content back online. His site mentions an upcoming daughter, and those of you with kids are already nodding your heads, because you know exactly how this story goes.
In any case, since there is currently no other place online to download this
code so far as I know, I dug up a tarball and mirrored it on GitHub.
You can get the latest code for op at tangledhelix/op.
My C skills are not up to par, so I am not currently planning to do anything with the code except host a copy of it. If Alec never gets back to it, and I decide to brush up on C in the future… well, we’ll see.
UPDATE: Dag Wieërs went to much more effort than I did and has set up a new repository tagged with versions of op all the way back to 1.1 in 1995. It’s actually pretty amusing to see a release date in 1995 on a GitHub page. I have removed my repo and will just point to his instead.