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| author | user <user@clank> | 2026-09-24 22:45:04 +0200 |
|---|---|---|
| committer | user <user@clank> | 2026-09-24 22:45:04 +0200 |
| commit | 4cd933009dd6ce87fe710acfca6b1f786d51040c (patch) | |
| tree | 67e50c2ab347ddc2ac3e5b6a5cf5a4cfc44cc8d0 /README.md | |
| parent | fs: mount the builtins at /bin (diff) | |
| download | gbos-4cd933009dd6ce87fe710acfca6b1f786d51040c.tar.gz gbos-4cd933009dd6ce87fe710acfca6b1f786d51040c.tar.xz gbos-4cd933009dd6ce87fe710acfca6b1f786d51040c.zip | |
usr: touch, tr, rev, cut, uniq
/# ls -l /bin > b
/# cut -d \s -f 1 b | uniq -c
52 -
- touch FILE...: gbfs has no timestamps (an MBC5 cart has no RTC), so touch
does the half that means something here - make an empty file. O_APPEND is
exactly right: it creates, and it does not truncate what is already there.
- tr [-d] SET1 [SET2]: ranges (a-z), -d to delete, and a short SET2 padded
with its last character, like tr(1). ASCII only - a 128-entry map.
- rev, uniq [-c]: one line each, from a file or stdin like the other filters.
Two things the tests caught. A bare "-" is a SET, not a flag, so `tr . -`
has to skip flag-matching only when a letter follows the dash. And uniq
compared an empty "line" against the last run at EOF and flushed a phantom
blank one - a stray "1" in uniq -c output.
tr and cut also take \s \t \n \r escapes, because the shell has no quoting:
`-d ' '` arrives as three tokens, so a space or tab delimiter was simply
untypeable. Shell quoting would be the better fix; this makes the tools
usable today without touching the parser.
Banks 49-53; 10 program slots left in the 1 MB ROM.
Diffstat (limited to 'README.md')
| -rw-r--r-- | README.md | 5 |
1 files changed, 3 insertions, 2 deletions
@@ -51,9 +51,10 @@ into the on-screen console. Regenerate it anytime with `tools/gbdemo` (below).* show up as one anyway — `ls /bin` enumerates the kernel's own command table, `cd /bin` works, and `xxd -l 16 /bin/uname` dumps the program's ROM bank. Read-only, since it is ROM. -- **A C toolchain**: userland is plain C compiled with SDCC (`sm83`); ~45 +- **A C toolchain**: userland is plain C compiled with SDCC (`sm83`); ~50 tools ship in `usr/` (`cat`, `wc`, `head`, `tail`, `grep`, `cp`, `mv`, - `tee`, `more`, `ls`, `df`, `xxd`, `sleep`, `uptime`, …) — `help` lists them all on + `tee`, `tr`, `cut`, `uniq`, `rev`, `more`, `ls`, `df`, `xxd`, + `touch`, `sleep`, `uptime`, …) — `help` lists them all on the Game Boy itself. Adding a program is one `.c` file + a table entry. ## Quick start |