C library functions are always like: "SYNOPSIS. This function converts foos into bars depending on the user locale. ARGUMENTS. src and dest pointers must be distinct; it is undefined behavior if they are not QPU-aligned. RETURN VALUE. Returns the number of foos converted. A zero value indicates failure, or that zero foos were converted. A negative value indicates that the final foo was only partially converted (function got tired). Check this global variable to find out why."
Hooley dooley.
This post is about a "found-in-the-wild" small Turing machine (3-states, 4-symbols), that halts --- after an Ackermann function-level number of steps; using Knuth's up-arrow notation, more than
\[ 14 \uparrow\uparrow\uparrow\uparrow\uparrow\uparrow\uparrow\uparrow\uparrow\uparrow\uparrow\uparrow\uparrow\uparrow 14
\]
and in fact we know exactly how many!
I operate by Crocker's rules[1].