collapseos/cvm/README.md

# C VM

This is a C implementation of Collapse OS' native words. It allows Collapse OS
to run natively on any POSIX environment.

## Requirements

You need `curses` to build the `forth` executable.

## Build

Running `make` will yield `forth` and `stage` executables.

## Usage

To play around Collapse OS, you'll want to run `./forth`. Refer to
`doc/intro.txt` for help.

The program is a curses interface with a limited, fixed size so that it can
provide a AT-XY interface. If you wish to change the size of that screen, you
need to modify COLS and LINES in both `forth.c` and `forth.fs`.

You can get a REPL by launching the program with [`rlwrap(1)`][rlwrap] like
this:

    rlwrap -e '' -m -S '> ' ./forth /dev/stdin

## Problems?

If the `forth` executable works badly (hangs, spew garbage, etc.),
it's probably because you've broken your bootstrap binary. It's easy to
mistakenly break. To verify if you've done that, look at your git status. If
`stage.bin` is modified, try resetting it and then run `make clean all`. Things
should go better afterwards.

A modified `blkfs` can also break things (although even with a completely broken
blkfs, you should still get to prompt), you might want to run `make pack` to
ensure that the `blkfs` file is in sync with the contents of the `blk/` folder.

If that doesn't work, there's also the nuclear option of `git reset --hard`
and `git clean -fxd`.

If that still doesn't work, it might be because the current commit you're on
is broken, but that is rather rare.

[rlwrap]: https://linux.die.net/man/1/rlwrap