MinorviewFs

From MinorFs Wiki

MinorViewFs is the initial owner of the full MinorCapFS tree. MinorViewFs creates and deletes sub directories and delegates sub directories to processes for private usage by mapping two symbolic links within the /mnt/minorfs/priv directory. The /mnt/minorfs/priv directory holds two distinct symbolic links:

• home
• tmp

The 'tmp' symlink points to a temporary directory that MinorViewFs has created on first access for the specific process that accesses it. Ones the process dies the tmp directory and all its sub directories, symlinks and data files will get deleted. Thus the tmp symlink points to a private tmp directory with the same lifetime as the process using it.

The 'home' symlink, the first time it is created seems to do exactly what the 'tmp' sysmlink does, but when the process dies it does not get deleted. MinorViewFs instead records the relevant information for identifying new instantiations of the same program under the same circumstances as new incarnations of the same pseudo persistent process. The next time the same program is started in the same way under the same uid, no new directory is created by MinorViewFs. Instead the old directory filled by the previous incarnation is delegated to the new incarnation.

If the process uses the 'home' directory for storing the serialization of its state, than the pseudompersistent process would in effect become a persistent process. The home directory can further be used to make delegations between processes permanent, and to keep application data secret from other processes.