SchOS/.claude/memory/schunix-usb-ids.md
Nexoniarz 57aff40228 docs: four directories, and a rule for when a thing leaves the roadmap
docs/ was ten files where a plan, a description, a guide and a bug report all
sat next to each other. It is now architecture/ (what SchOS is), plan/ (what it
will be), guides/ (how to work on it) and history/ (why it is like this), with
an index that states the one rule holding it together: when something is
finished it moves from plan/ to architecture/ and is rewritten as a description
of the thing rather than a record of building it.

A ticked checkbox says the work happened. It does not say what the work
*produced*, and six months later the checkbox is all that is left. The network
stack proved the point: finished, verified end to end, and for a month the only
description of it anywhere was a checkbox four levels of indentation deep.

So roadmap.md went from 534 lines to 181 -- nothing deleted, the done work
graduated. Seven subsystems that were finished and undescribed now have
descriptions: boot, kernel, syscalls, filesystem, networking, graphics, usb,
init. Every one ends with "What it does not do", which is the section that pays;
a document listing only strengths is marketing, and the reader who needs it most
is the one about to trip over a limitation nobody wrote down.

schfs.md still opened with "phases 1 through 3 1/2 are done, phase 4 is next"
long after all five had landed. It is a description now, with the phase record
and the hard-won bugs moved to history/.

Three corrections found on the way, all load-bearing:

  * projects/schcom/README.md claimed SCM_RIGHTS was done. There is no
    sendmsg/recvmsg in the kernel at all, and an entire GUI plan rested on it.
  * The root README said "No TCP/IP" months after the stack landed.
  * history/kernel.md sec.7 was marked "in progress" on a problem that process
    groups solved.

Also adds plan/1.0.md, which draws a finish line so the open list stops being
infinite, and marks schwm/ and schde/ superseded: in Wayland the compositor is
the window manager, so that split dissolves rather than being abandoned.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VQ7Qx8E1q1M1bbCq8QLHS2
2026-09-12 17:13:35 +02:00

45 lines
2.3 KiB
Markdown

---
name: schunix-usb-ids
description: "usb.ids ships as /usr/share/usb.ids, cached in dist/ and refreshed with `make usb-ids` — deliberately not on every build."
metadata:
node_type: memory
type: project
originSessionId: 9d8a2aef-bcf0-47a0-96c6-f706efab4a95
modified: 2026-08-08T22:10:41.961Z
---
Added 2026-08-09 at Nexoniarz's request. `dist/usb.ids` →
`sysroot/usr/share/usb.ids`, 730 KB, 25,673 lines, version 2026.06.26.
**Licence: dual GPL-2.0-or-later OR 3-clause BSD.** The file's own header says
nothing; the statement is on <http://www.linux-usb.org/usb-ids.html>: "under the
terms of either the GNU General Public License (version 2 or later) or of the
3-clause BSD License." Schunix takes the **BSD** option — the GPL one could not
be exercised, since Apache-2.0 and GPL-2.0-only cannot be combined. `NOTICE`
carries the attribution and says which option was taken.
## Two places I deliberately did not do what was asked
**"Update every compilation."** It is cached in `dist/` and refreshed only by
`make usb-ids`. Fetching per build would break offline builds, make the same
source produce different images on different days, and put a third-party web
server on the critical path of `make` — and `dist/` exists precisely so a
rebuild never needs the network (stated in `docs/guides/layout.md`). The file is
committed and carries its own version and date, so what shipped is always
knowable. The update target validates the download (`grep -q "^# Version:"`)
before replacing the cached copy, so a truncated file or an error page cannot
silently destroy a good database.
**It is not in the kernel.** 730 KB against a ~770 KB kernel. Linux does not do
this either — the kernel reports vendor:product and `lsusb` resolves names from
`/usr/share/hwdata/usb.ids` in userspace. Same split here: `/proc/devices` and
the USB core report IDs; a future `lsusb` reads the database.
Also added to `RAMDISK_EXCLUDE` — 730 KB is 12% of the 6 MB ramdisk root and
nothing needs it to boot. Verified: `mkfs: excluding usr/share/usb.ids`, ramroot
metadata unchanged at 345 blocks. This is the second real use of that mechanism
(see [[schunix-ramdisk-root-sizing]]).
**Still to do:** nothing reads it yet. An `lsusb` in `cmd/` that walks the USB
core's device list and looks names up is the natural next step, and would make
`/proc/devices` far more legible than `1234:1111`.