https://driverlesscrocodile.com/technology/neal-stephenson-o...

I wish it were this simple.

The em square != the bounding box of all glyphs. The em square is defined by the font's ascent & descent vertical metrics, which are set by the font designer.

There are reasons why you might want glyphs to escape the em square. Perhaps you're typesetting English text without accent marks above capitals, and using the bounding box's vertical maximum would introduce too much line space. Or perhaps you're using a decorative font which is designed to escape the em square, and potentially even overlap the em squares of lines above and below, like this: https://alangrow.com/images/blog/script-font-escaping-em-squ...

To make matters worse, and mostly for legacy reasons, there are THREE different sets of ascent & descent metrics in a font file. Which is used depends on your OS and the software rendering the font. But the Webfont Strategy described here is a nice one, because you can use the bounding box (winAscent & winDescent) if you really need to, say because any glyph might be used and you want to avoid em square escape: https://glyphsapp.com/learn/vertical-metrics

Comments URL: https://news.ycombinator.com/item?id=44424732

Points: 1

# Comments: 0

  # Proxy to a backend server based on the hostname.
  if (-d vhosts/$host) {
    proxy_pass http://unix:vhosts/$host/server.sock;
    break;
  }

Not a single command, and you still have to add hostname resolution. But you don't have to programmatically edit config files or restart the proxy to stand up a new dev server!

https://www.gallery.ca/magazine/your-collection/a-familiar-f...

Around this time my co-conspirator and I realized the library had 386s that almost no one was using for catalog search. They became our fractal render farm. We'd exit the catalog program, insert a floppy with our latest renderer, kick off a deep zoom, and turn off the monitors to avoid suspicion until we could check back next period. The results were thrilling. What a difference the access to compute made.

You all know the story -- eventually the librarian found us out and reported us for "hacking."

Comments URL: https://news.ycombinator.com/item?id=41113268

Points: 3

# Comments: 1

Got curious about this recently. I’m not great at citation tracing, but did make it back to this 1995 paper by David Eppstein [0] where he uses it to efficiently solve Subset Sum after an incremental update. Surely Knuth’s TAOCP had it even earlier?

The fact that FFT polynomial multiplication also lets you solve Exact Subset Sum with Repetition in sub-exponential time came as a real shock to me. [1] Crucially, this algo is O(N log N) where N = the maximum element, not N = the set size, so it isn’t a P ≠ NP counterexample or anything.

[0] https://escholarship.org/content/qt6sd695gn/qt6sd695gn.pdf

[1] https://x.com/festivitymn/status/1788362552998580473?s=46&t=...

More often than I’d like! tmux config has broken backwards compatibility on me multiple times over the years.

This is fine for most software — you upgrade your config once and you’re done. However, the nature of tmux is that I use it on many servers, some old and some new, some with tmux 1.x and some with 2.x. Getting a ~/.tmux.conf from my dotfiles repo that works across both has been papercutty.

Love tmux though & can’t imagine tty life without it — I run it locally as well as on remote machines.

Szabo also takes this up in his excellent essay "A Measure of Sacrifice":

Fair broadcast and verification of time was thus of fundamental importance to the most common contractual relationship in the new European cities. In agricultural societies, including medieval Europe, serfdom and slavery had provided most of the labor. Most workers in a modern economy earn wages based on a time rate. Along with or following the rise of the time-rate institution – including the contracts themselves, the laws and regulations governing the contracts, and the technology to fairly measure the principal quantity – came the growth of related economic institutions, such as the joint stock company. These institutions enabled a boom in productivity and the spectacular rise of Europe from its darkest ages to the modern era. We will now chart the rise of the clocks and the institutions they supported.

https://www.fon.hum.uva.nl/rob/Courses/InformationInSpeech/C...

Derivatives of RegExps don't automatically unlock parsing of context-free grammars, afaik. For that you need recursion. They do however unlock some very elegant parser designs.

[0] https://en.wikipedia.org/wiki/Context-free_grammar

[1] https://en.wikipedia.org/wiki/Regular_grammar

[0] https://matt.might.net/papers/might2011derivatives.pdf

[0] https://transloadit.com/

https://gitlab.freedesktop.org/dbus/dbus/-/blob/master/dbus/...

> Meaning you have to be incredibly careful what you do when creating the socket and you cannot really pass any sockets off to other processes if you want to try to do security that way because they will still inherit the wrong credentials.

I see nothing new here beyond "handle privileged resources with care." Don't overshare. Got an open pipe to `sh` running as root? Maybe you oughtta set O_CLOEXEC on that fd before you exec and overshare with a child. Got a socket that's been peer authed? The same.

This is pretty basic unix stuff. If you stick to the basics and avoid the siren call of complexity, the security properties remain relatively easy to reason about. Most privileged resources are fds. Mind your fds.

I'm not a huge fan of sending file descriptors over sockets – maybe we agree on that part.