US Patent 12135896 Side-effect resistant operation testing

Operation testing without side effects may be enabled by a method including preparing a copy of a directory set of at least a part of a host system disk, creating a link to a file in a first directory in the host system disk, in a second directory of the copy of the directory set, wherein the second directory corresponds in position to the first directory in the directory set, and starting a non-privileged system using a disk image including the copy of the directory set and the created link.