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/help.c?h=master 2026-09-24T10:48:51Z 2026-09-24T10:48:51Z user user@clank 2026-09-24T10:48:51Z urn:sha1:65b53de14dc6918db39b6ee6dc032f805182daad Filling in the core utilities the box was missing: - ls -l: type, links and size, now that stat() exists. The screen is 40 columns, so it is "d 1 256 name", not the GNU sprawl. Sizes were previously unknowable except one file at a time with wc -c. - df: blocks and inodes, used and free, on the 32 KiB cart disk. - mv: no rename syscall, so it is cp + rm - and the copy has to finish before the source goes, or a failure loses the file. - tail [-n N]: no seek syscall, so it streams the input through a ring of N lines rather than jumping to the end. N is capped by that ring. - tee: the missing half of a pipeline - `cat big | tee copy | wc -l`. - sleep: the thing every script needs; the kernel counts 1/64 s ticks. - help: lists every command the shell knows, walked out of the kernel's own name table. The box previously had no way to tell you what it could do. - poweroff: the only safe way to stop a gbos that has data on it. The cart's battery RAM is written when the emulator exits cleanly, so killing it loses the whole filesystem - it comes back "formatted". Found while testing /rc.