2.5 Virtual File System
The Virtual File System (VFS) enables your target to access parts of a host filesystem, through a target OS-specific driver and a memory-mapped device called the MessageBox. Access to the host filesystem is analogous to access to a shared network drive.
The VFS supports these filesystem operations:
- Retrieve metadata for the file, directory or symbolic link.
- Create a new directory.
- Remove a file, directory or symbolic link.
- Rename a file, directory or symbolic link.
- Remove an empty directory.
Set metadata for the file, directory or symbolic link.
NoteThe VFS does not implement
The VFS does not support symbolic links. The model cannot create hard links but those that
the host operating system creates do function correctly.
The VFS supports these mount points:
Free the iterator handle returned from
- Retrieve an iterator handle for the list of available mounts.
- Read one entry from the mount iterator ID.
The VFS supports the following directory iterators:
- Free a directory iterator handle retrieved by
- Retrieve an iterator handle for the directory specified.
- Read the next entry from the directory iterator.
Datestamps returned are in milliseconds elapsed since the
VFS epoch of January 01 1970 00:00 UTC and are host datestamps.
The host datestamp might be in the future relative to the simulated OS
The VFS supports these file operations:
- Free a handle opened with
- Force the host OS to flush all file data to persistent storage.
- Return the size of a file, in bytes.
- Return a handle to the file specified.
- Read a block of data from a file.
- Set the size of a file in bytes, either by truncating, or extending the file
- Write a block of data to a file.