Arrow-key navigation took 435 ms per keypress, which reads as the whole console
reloading on every press - because it effectively was. The cost was forks: each
frame ran a command substitution per label for the value, the translation and
the rendered state, 54 subshells for eighteen rows.
The frame is now assembled in memory and written once. Translations, the split
specs and the terminfo clear string are resolved before the loop; values are
re-read only after something actually changes, not on cursor movement. Helpers
on that path assign to a variable instead of printing, since printing is what
forced the substitution.
Measured on the same machine: 435 ms -> 7.5 ms per keypress.
All eighteen options are now reachable from the menu as a cursor list: arrows
select, Space or Right cycles a value, q goes back, changes are written
immediately. A numbered menu would have run out of digits.
Three real bugs surfaced while building it, each found by testing against an
actual pty rather than a pipe:
- Labels went through printf as format strings, so the percent sign in
"Minimum battery level (%)" was an invalid conversion. cau_msg_in now only
treats a message as a format string when arguments were actually passed -
otherwise any literal % a translator writes is a trap.
- Mixing bash's line-mode read into a single-key interface left the following
read -sn1 receiving nothing at all, reproducibly, so the screen froze after
editing the package list. Replaced with a small line editor built on the same
single-character reader.
- Backspace was being swallowed: in canonical mode DEL is the ERASE character
and the line discipline consumes it, and bash returns to canonical mode
between each read -sn1. The interface now holds non-canonical mode for its
whole lifetime and hands the terminal back only around actions that print or
prompt, with a trap restoring it on Ctrl-C.
Translations and config reads are memoized; the screen redraws every label on
every keypress and a fork per lookup was the reason the redraw was slow enough
to matter.
A run that held back a blocker then upgraded 214 packages printed one line and
then nothing for nearly five minutes while pacman downloaded and installed. It
looked hung, so it got killed - during pacman's uninterruptible commit phase,
which meant the packages landed but our bookkeeping never did. The menu then
kept showing a failure from a previous run on a fully up-to-date machine.
pacman, the AUR helper and flatpak now stream their output when a person is
watching, and the progress bar is left enabled for that case. Timer runs are
unchanged: quiet, --noprogressbar, everything captured in the log.
Interactivity is decided once at startup rather than tested at the point of
use. cau_pacman_flags runs inside a process substitution, so its stdout is
always a pipe and a -t 1 check there would have silently always been false.
INT/TERM/HUP now record last_result=interrupted, so a run that is stopped says
so instead of leaving the previous verdict standing.
Toggling automatic updates or notifications returned to a 'press any key'
prompt for no reason - the status block at the top of the menu already shows
the new state. cau_bad and cau_note now flag that they printed something, so
the acknowledgement only appears when there is genuinely something to read
(a failed sudoers check, a missing AUR helper) instead of after every toggle.
A root systemd service applies pacman, AUR, Flatpak and AppImage updates on
its own, gated on battery state, gaming activity and whether anybody else is
using the package system. The CLI is deliberately two switches plus status.
No user password is stored anywhere: pacman runs as root directly, and the AUR
step - which makepkg forbids running as root - drops to a locked system account
that sudoers permits to call pacman without a password.
Felitendo