ABSTRACT
The central entity in UNIX is a file — every activity on the system represents some kind of transaction with or between files. Consequently, administrators of UNIX systems are expected to deal with files, including the special purpose files known as configuration files. Configuring system functions, setting some system parameters, tuning a kernel, and restoring a lost file, all require the appropriate access to the needed data within the file. On the other side, system files always require privileged access. In practice, this means that the administrator has to be a superuser on the system in order to effectively administer the UNIX system.
