gbos - a tiny Unix-flavored OS for the Game Boy Color (kernel, shell, coreutils in C, RAM filesystem) https://git.sl0p.foo/gbos.git/atom/usr/ircd.c?h=master 2026-09-24T11:09:34Z 2026-09-24T11:09:34Z user user@clank 2026-09-24T11:09:34Z urn:sha1:a73911fcbc5d7d6910d1edcdca38230a519361ca NICK overwrote the nick with whatever was asked for, so two clients could both be "alice": /NAMES listed her twice and a private message only ever reached whichever slot came first in the table. - A nick already held by another client is refused with 433 ERR_NICKNAMEINUSE and the client keeps the one it had. Unregistered clients simply stay unregistered until they pick a free one, which is what every client already expects. - A NICK from a registered client is a rename: it is announced to the client and to its channel, so nobody's user list goes stale. - IRC names fold case, so "Alice" is "alice" - for the uniqueness check, for PRIVMSG by nick, and for channels ("#GB" is "#gb"). One irceq() replaces the exact-match compare that was used for all three. gbos's own irc(1) already retries 433 by appending '_', so two Game Boys with the default nick now sort themselves out: verified with a GB running ircd, a laptop client holding "sl0pboy", and a second GB arriving as "sl0pboy_" - both in #gbos, messages crossing both ways. 2026-09-22T19:54:13Z user user@clank 2026-09-22T19:54:13Z urn:sha1:0a7ff09a910eaf5bcb0dc76d08dc5a6c9c239495 /# ircd & host$ irssi -c 10.0.0.2 /join #gbos other GB$ irc 10.0.0.2 gb2 /join #gbos Implements the subset a real client needs to get in and talk: NICK, USER, PING/PONG, JOIN, PART, PRIVMSG/NOTICE (to a channel or to a nick), NAMES and QUIT, with the 001/004/375/372/376 numerics clients wait for on registration, 353/366 on join, and 421 for anything else. One channel per client keeps the bookkeeping in fixed-size tables; this is a handheld with 8 KiB of task RAM. MAXCL is 3, bounded by the kernel socket table (listener + client each take a slot, the rest left for other programs). A fourth client is refused and the daemon keeps serving - which is how the ~30s close() stall turned up. Every event is logged to the LCD, so the Game Boy shows its own server traffic: "+ alice", "alice joined", "<alice> hello". Verified with real clients over the hub: two and three simultaneous hosts registering, joining, channel relay (sender not echoed to itself), private messages by nick, PING/PONG, unknown-command numerics, QUIT propagation, the overflow refusal, and a second Game Boy running gbos's own irc(1) in the same channel as a laptop client - messages crossing both ways between them.