Simple 9p server that adds a copy on write layer to an existing filesystem.

Invoke with:

cow9p -s src -d dst

This will start a 9p server (by default listening on tcp port 5640). Any non-disctructive file operations will try to use the filesystem dst, and will use src as a fallback if the necessary files do not exist on dst. For destructive operations (e.g. write) dst will again be used, first, but if the files are not found, the will be copied to dst from src, rather than operating on src directly.

Work in progress. Idea is well defined, but it doesn't work yet. The interfaces are not considered stable either.

Use at your own risk.

MIT license. see COPYING.