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Comment by p_l | Hacker News Reader

Simple reason - there was no way to do feature detection reliably on many a terminal, which also makes me wondering how the hell are they going to make it reliable, unless they simply decide to not support many terminals.

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The key is ending the device query string with DA1 aka "Primary Device Attributes", which literally every terminal i've managed to test with responds to. Guaranteed that one answer, you completely avoid nasty timeouts. This is required for even VT100 conformance, so it can be expected on even hardware terminals (though not necessarily those outside the DEC family).

I tested over 24 terminals personally, and the only one I found which didn't respond to DA1 was Terminology from EFL, which crashed forty ways to a friday anyway so who really cares?

i'm glad you asked, as i'm hella proud of this entire system. you can check the code at:

https://github.com/dankamongmen/notcurses/blob/master/src/li...

and

https://github.com/dankamongmen/notcurses/blob/master/src/li...

i mean, it's tricky, and you have to think some things out pretty carefully, but it works. everything hinges on DA1.

many props to @dknl of the "foot" terminal emulator, who just kicks ass in general and first turned me on to DA1:

you can see the history in bugs starting with https://github.com/dankamongmen/notcurses/issues/1469

hack on!

From the change log:

> Numerous patches were submitted to upstream terminals to support this functionality.

That's still going to lose the long tail

Sure, then you just fall back to whatever best effort approach you were using before.

At some point, the number of people on that tail will be smaller than the number of people with an incorrectly setup $TERM, for a net gain in effective portability.

It’s often so easy not to submit these kinds of changes. But 10 years later you still don’t have them.

Seems like a long wait now but is worth it later.

They won't support that many terminal types. This is what has been done in this situation for decades.

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