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MVH Kernel mounts a RAMFS (RAM-based filesystem) as the root filesystem at boot. The filesystem lives entirely in kernel memory, so it is fast and requires no disk hardware, but it is completely volatile — every file and directory you create is lost the moment you reboot. Use it to hold temporary text, test path navigation, or exercise the VFS layer during a session.
All files and directories are reset on every boot. RAMFS does not persist data across reboots.

Filesystem limits

The following constants define the hard limits of the RAMFS implementation (from include/mvh/fs.h):

ls

List the contents of a directory. Syntax
If you omit path, the current working directory is listed. Directories are shown with a [DIR] prefix in blue; files are shown with [FILE] and their size in bytes. Example

dir

Alias for ls. Accepts the same optional path argument and produces identical output. Syntax
Example

cd

Change the current working directory. Both relative and absolute paths are supported. Running cd without an argument changes to /home. Syntax
Examples
If the directory does not exist, the shell prints cd: directory not found.

pwd

Print the current working directory as an absolute path. Syntax
Example

mkdir

Create a new directory at the given path. Parent directories must already exist. Syntax
Example
If the path is invalid or a parent directory is missing, the shell prints mkdir: cannot create directory.

touch

Create a new empty file. If the file already exists, the command succeeds without modifying its contents. Syntax
Example

write

Write text to a file, replacing any existing content. If the file does not already exist, it is created automatically. The entire argument after the filename is treated as the text to write. Syntax
Example
If the text exceeds the 256-byte file limit, the shell prints write: file is full.

append

Append text to an existing file without removing previous content. If the file does not exist, it is created first. The total file size must remain within FS_DATA_MAX (256 bytes). Syntax
Example

cat

Print the full contents of a file to the shell. Syntax
Example
If the file does not exist, the shell prints cat: file not found.

type

Alias for cat. Accepts the same path argument and produces identical output. Syntax
Example

open

Open a file and print its contents. Behaves identically to cat. Syntax
Example

rm

Remove a file from the filesystem. The path must point to an existing file, not a directory. Syntax
Example
If the path is not found, the shell prints rm: path not found. If you attempt to remove a non-empty directory, the shell prints rm: directory is not empty.

rmdir

Remove a directory. The directory must be empty before removal. rmdir is an alias that calls the same underlying removal function as rm. Syntax
Example
If the directory is not empty, the shell prints rmdir: directory is not empty.

mount

List all currently mounted filesystems. In the current release, RAMFS is the only filesystem and is always mounted at /. Syntax
Example

df

Display filesystem usage information. In the current release this shows the RAMFS root entry only. Syntax
Example