root (/)

UFS

The top of the hierarchical file tree. The root (/) directory contains the directories and files that are critical for system operation, such as the kernel, the device drivers, and the programs used to boot the system. The root (/) directory also contains the mount point directories where local and remote file systems can be attached to the file tree.

/usr

UFS

System files and directories that can be shared with other users. Files that run only on certain types of systems are in the /usr file system (for example, SPARC executables). Files that can be used on all types of systems, such as the man pages, are in the /usr/share directory.

/export/home or /home

NFS, UFS

The mount point for user home directories, which store user work files. By default, the /home directory is an automounted file system. On stand-alone systems, the /home directory might be a UFS file system on a local disk slice.

/var

UFS

System files and directories that are likely to change or grow over the life of the local system. These include system logs, vi and ex backup files, and uucp files.

/opt

NFS, UFS

Optional mount point for third-party software. On some systems, the /opt directory might be a UFS file system on a local disk slice.

/tmp

TMPFS

Temporary files, which are removed each time the system is booted or the /tmp file system is unmounted.

/proc

PROCFS

A list of active processes, by process number.

/etc/mnttab

MNTFS

A virtual file system that provides read-only access to the table of mounted file systems for the local system.

/var/run

TMPFS

A memory-based file system for storing temporary files that are not needed after the system is booted.

/system/contract

CTFS

A virtual file system that maintains contract information.

/system/object

OBJFS

A virtual file system that is used by debuggers to access information about kernel symbols without having to access the kernel directly.