fakeroot:tldr:0ffd3

The fakeroot command is used to run commands or build software packages as if being executed as the root user, without actually requiring root privileges. It provides a "fake root" environment where certain operations that typically require root access can be carried out by a non-privileged user.

When you run a command with fakeroot, it intercepts file system operations such as file creation, modification, and deletion, and keeps track of these operations in a file called the "filesystem metadata file". This file records all the changes that would have been made by the program if it were actually run as root.

The primary use of fakeroot is in the process of creating software packages, such as Debian packages (.deb files). Package maintainers can use fakeroot to build the package without needing root access, as it allows them to create the necessary directory structures, modify files, and set permissions as if they were running as root.

By using fakeroot, developers can test and package software without risking accidental damage to the system, as the changes made during the execution of the command are confined to the metadata file and do not affect the actual system files.

Note that fakeroot only affects file system operations and does not grant any other root privileges. It is mainly used to create a "safe" environment for certain operations, such as building packages.