gbos.git/c/chat.c, branch master 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/c/chat.c?h=master 2026-07-17T22:38:38Z refactor: c/ -> usr/, compiled program blobs out of the source tree 2026-07-17T22:38:38Z user user@clank 2026-07-17T22:38:38Z urn:sha1:ba2d7ae1d7b319645b10aaa31a7f664f9f80c25c Userland sources live in usr/ (fits the Unix theme better than 'c'). SDCC output .bin blobs land in build/usr/ with the other build artifacts instead of littering the source dir; programs.asm INCBINs them from there. Byte-identical ROM. net: chat client - async receive + OSK send over the link port 2026-07-16T23:39:29Z user user@clank 2026-07-16T23:39:29Z urn:sha1:c4b9a1b1c4f8c211f765a089b34b66a2d046f3be The application layer of the link-port demo, and it ties the whole system together: the LCD terminal displays, the on-screen keyboard types, and the link port carries a live chat. Kernel: sys_srecv_nb (non-blocking link receive; A=byte, CF=none) and sys_pollin (poll the OSK for a typed char without blocking) - syscalls 31/32. Both are what a poll loop needs to receive and type at once. Userland: c/chat.c runs a poll loop - it feeds non-blocking bytes through a SLIP receive state machine and prints whole incoming frames as messages, while pollin() drives the on-screen keyboard; SELECT shows the keys, type a line, START sends it as a frame. libc srecv_nb()/pollin(). Host: tools/gateway.py --mode chat is a simple bot peer (echoes each GB message and injects a few async ones); --keys can drive the OSK for tests. Verified: the gateway pushes 'welcome', '<alice> hey gameboy!', '<bob> nice link cable' unprompted and the GB displays all three (async receive); typing 'hi' on the OSK echoes it and emits the SLIP frame \xC0hi\xC0 (send). A Game Boy in the chat, keyboard on screen, over the link cable.