In a few instances, features in SVR4 were not include in the Solaris operating environment. These features are specific to AT&T hardware, or features included primarily for backward compatibility with SVR3 features and are, therefore, of little value to SunOS users.
The Solaris operating environment does not include the System V file system and associated utilities because of their limitations compared to the UNIX file system. The SVR4 boot file system was not included because of its maintenance burden when compared to the SunOS traditional boot model.
The generic AT&T SVR4 model for device auto-configuration and for rebuilding kernels was replaced with a fully dynamically configurable kernel better suited to the needs of present and future users of SPARC systems.
The Solaris operating environment does not include the AT&T SVR4 sysadm utility. Because the sysadm menu utility was designed primarily for use with terminal devices on freestanding systems, GUI tools are used instead to simplify administration of distributed systems across a network. The Solaris operating environment provides the utilities and configuration directories that underlie the SVR4 sysadm utility but not the sysadm utility itself.