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Reset on a gesture the host has no opinion about

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Control, Shift and R. It was Control, Alt and Delete, which brings up a shutdown prompt
rather than reaching the machine - and no amount of asking will change that.

IT IS A SECURE ATTENTION KEY. Every serious operating system reserves it so that it always
reaches the system and never an application, precisely so a program cannot imitate a login
screen. On Windows an application cannot see it without a kernel driver; on Linux the desktop
takes it. That is not an oversight to work around, it is the same guarantee a reset button
wants being enforced one layer further down, and there is no call this program could make
that would win the argument. It is unavailable for exactly the reason it seemed right.

So the requirement list grew a third item that was not obvious until it bit: the gesture has
to be one the host has no opinion about. Control and Shift with a letter is about as free as
a combination gets - not window management, not a virtual terminal switch, and not a shortcut
any desktop claims by default. It keeps the other two properties: plain F12 and plain Delete
stay free for software, and three keys are not pressed by accident.

If some platform does send a character for it, nothing comes of that either. Whatever arrives
is in memory that is about to be thrown away.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW
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Anachronaut
2026-08-29 14:41:05 -04:00
co-authored by Claude Opus 5
parent 0afead00de
commit 8c6ed62044
2 changed files with 30 additions and 9 deletions
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@@ -47,12 +47,19 @@ The suite holds the two to being the same machine rather than taking it on trust
the entire manifest through Voyager as well, with `--headless`, and requires it to satisfy
every recorded result byte for byte.
**Control, Alt and Delete is the reset button.** On real hardware it is not a key at all - a
Voyager has a button on the case, and what a window has instead of a case is a gesture. Two
**Control, Shift and R is the reset button.** On real hardware it is not a key at all - a
Voyager has a button on the case, and what a window has instead of a case is a gesture. Three
things follow from that. It must not be a key software might want, because a machine with a
keyboard has function keys and something will eventually have a use for them. And it must not
be reachable by accident, because restarting throws away everything in memory and a single
key that does that sits one mistake away from losing work.
keyboard has function keys and something will eventually have a use for them. It must not be
reachable by accident, because restarting throws away everything in memory and a single key
that does that sits one mistake away from losing work. And **it must be a gesture the host
has no opinion about**.
That last one rules out the obvious answer. Control, Alt and Delete has meant this since 1981
and cannot be used: it is a secure attention key, reserved by every serious operating system
so that it always reaches the system and never an application - precisely so a program cannot
imitate a login screen. On Windows an application cannot see it without a kernel driver, and
on Linux the desktop takes it. It is unavailable for the same reason it seemed right.
It does exactly what writing to the machine port does: the machine starts the way it started,
so the boot chain runs again and finds whatever the disk now says to run.