NAME

filesystem - file system organization

SYNOPSIS

/

/usr
/export

DESCRIPTION

The file system tree is organized for administrative convenience. Distinct areas within the file system tree are provided for files that are private to one machine, files that can be shared by multiple machines of a common architecture, files that can be shared by all machines, and home directories. This organization allows sharable files to be stored on one machine but accessed by many machines using a remote file access mechanism such as NFS. Grouping together similar files makes the file system tree easier to upgrade and manage.

The file system tree consists of a root file system and a collection of mountable file systems. The mount (2)program attaches mountable file systems to the file system tree at mount points (directory entries) in the root file system or other previously mounted file systems. Two file systems, / (the root) and /usr, must be mounted in order to have a completely functional system. The root file system is mounted automatically by the kernel at boot time; the /usr file system is mounted by the system start-up script, which is run as part of the booting process.

Root File System

The root file system contains files that are unique to each machine. It contains the following directories:

/dev

Primary location for special files. Typically, device files are

built to match the kernel and hardware configuration of the

machine.

/dev/dsk

Block disk devices.

/dev/pts

Pseudo-terminal devices.

/dev/rdsk

Raw disk devices.

/dev/rmt

Raw tape devices.

/dev/sad

Entry points for the STREAMS Administrative driver.

/dev/term

Terminal devices.

/etc

Host-specific administrative configuration files and data-

bases. /etc may be viewed as the directory that defines the

machine's identity.

/etc/acct

Accounting system configuration information.

/etc/cron.d

Configuration information for cron (1M).

/etc/default

Defaults information for various programs.

/etc/dfs

Configuration information for exported file systems.

/etc/fs

Binaries organized by file system types for operations

required before /usr is mounted.

/etc/inet

Configuration files for Internet services.

/etc/init.d

Shell scripts for transitioning between run levels.

/etc/lib

Shared libraries needed during booting.

/etc/lp

Configuration information for the printer subsystem.

/etc/mail

Mail subsystem configuration.

/etc/net

Configuration information for transport independent net-

work services.

/etc/opt

Configuration information for optional packages.

/etc/rc0.d

Scripts for entering or leaving run level 0. See init(1M).

/etc/rc1.d

Scripts for entering or leaving run level 1. See init(1M).

/etc/rc2.d

Scripts for entering or leaving run level 2. See init(1M).

/etc/rc3.d

Scripts for entering or leaving run level 3. See init(1M).

/etc/saf

Service Access Facility files.

/etc/skel

Default profile scripts for new user accounts. See

useradd(1M).

/etc/sm

Status monitor information.

/etc/sm.bak

Backup status monitor information.

/etc/tm

Trademark files; contents displayed at boot time.

/etc/uucp

UUCP configuration information. See uucp(1C).

/export

Default root of the exported file system tree.

/home

Default root of a subtree for user directories.

/kernel

Subtree of Platform Independent loadable kernel modules

required as part of the boot process. It includes the generic

part of the core kernel that is platform-independent,

/kernel/genunix. See kernel(1M).

/mnt

Default temporary mount point for file systems. This is an

empty directory on which file systems may be temporarily

mounted.

/opt

Root of a subtree for add-on application packages.

/platform

Subtree of Platform Specific objects which need to reside on

the root filesystem. It contains a series of directories, one per supported platform. The semantics of the series of direc-

tories is equivalent to / (root).

/platform/* /kernel

Platform Dependent objects with semantics equivalent to

/kernel. It includes the file unix ,the core kernel that is plat-

form dependent. See kernel(1M).

/platform/* /lib

Platform Dependent objects with semantics equivalent to

/lib.

/platform/* /sbin

Platform Dependent objects with semantics equivalent to

/sbin.

/proc

Root of a subtree for the process file system.

/sbin

Essential executables used in the booting process and in

manual system recovery. The full complement of utilities is

available only after /usr is mounted.

/tmp

Temporary files; cleared during the boot operation.

/var

Root of a subtree for varying files. Varying files are files that are unique to a machine but that can grow to an arbitrary

(that is, variable) size. An example is a log file.

/var/adm

System logging and accounting files.

/var/cron

Log files for cron (1M).

/var/mail

Directory where users' mail is kept.

/var/news

Community service messages. Note: this is not the same as

USENET-style news.

/var/nis

NIS+ databases.

/var/opt

Root of a subtree for varying files associated with optional

software packages.

/var/preserve

Backup files for vi(1) and ex (1).

/var/sadm

Databases maintained by the software package management utilities.

/var/saf

Service access facility logging and accounting files.

/var/spool

Root directory for files used in printer spooling, mail

delivery, cron (1M),at(1), etc.

/var/spool/cron

cron (1M)and at(1) spooling files.

/var/spool/locks

Spooling lock files.

/var/spool/lp

Line printer spool files. See lp(1).

/var/spool/mqueue

Mail queued for delivery.

/var/spool/pkg

Spooled packages.

/var/spool/uucp

Queued uucp(1C) jobs.

/var/spool/uucppublic

Files deposited by uucp(1C).

/var/tmp

Transitory files; this directory is not cleared during the boot

operation.

/var/uucp

uucp(1C) log and status files.

/var/yp

Databases needed for backwards compatibility with NIS and ypbind(1M); unnecessary after full transition to NIS+.

/usr File System

Because it is desirable to keep the root file system small and not volatile, on disk-based systems larger file systems are often mounted on /home, /opt, /usr, and /var.

The file system mounted on /usr contains architecture-dependent and architectureindependent sharable files. The subtree rooted at /usr/share contains architectureindependent sharable files; the rest of the /usr tree contains architecture-dependent files. By mounting a common remote file system, a group of machines with a common architecture may share a single /usr file system. A single /usr/share file system can be shared by machines of any architecture. A machine acting as a file server may export many different /usr file systems to support several different architectures and operating system releases. Clients usually mount /usr read-only so that they do not accidentally change any shared files.

The /usr file system contains the following subdirectories:

/usr/4lib

a.out libraries for the Binary Compatibility Package. See

Binary Compatibility Guide.

/usr/bin

Primary location for standard system utilities.

/usr/bin/sunview1

SunView executables. This directory is only present when

the Binary Compatibility Package is installed.

/usr/ccs

C compilation system.

/usr/ccs/bin

C compilation commands and system utilities.

/usr/ccs/lib

Libraries and auxiliary files.

/usr/demo

Demo programs and data.

/usr/dt

root of a subtree for CDE Motif.

/usr/dt/bin

Primary location for CDE Motif system utilities.

/usr/dt/include

Header files for CDE Motif.

/usr/dt/lib

Libraries for CDE Motif.

/usr/dt/man

On-line reference manual pages for CDE Motif.

/usr/games

Game binaries and data.

/usr/include

Include headers (for C programs, etc).

/usr/kernel

Subtree of Platform Independent loadable kernel modules,

not needed in the root filesystem.

/usr/platform

Subtree of Platform Specific objects which does not need to

reside on the root filesystem. It contains a series of direc-

tories, one per supported platform. The semantics of the

series of directories is equivalent to /platform, except for

subdirectories which don't provide utility under one or the

other (for example: /platform/include isn't needed).

/platform/* /include

Platform Dependent headers with semantics equivalent to

/usr/include.

/platform/* /kernel

Platform Dependent objects with semantics equivalent to

/usr/kernel.

/platform/* /lib

Platform Dependent objects with semantics equivalent to

/usr/lib.

/platform/* /sbin

Platform Dependent objects with semantics equivalent to

/usr/sbin.

/usr/lib

Program libraries, various architecture-dependent databases, and executables not invoked directly by the user (system

daemons, etc).

/usr/lib/acct

Accounting scripts and binaries. See acct(1M).

/usr/lib/dict

Database files for spell(1).

/usr/lib/class

Scheduling class-specific directories containing executables

for priocntl(1) and dispadmin(1M).

/usr/lib/font

troff(1) font description files.

/usr/lib/fs

File system type dependent modules; generally not intended to be invoked directly by the user.

/usr/lib/iconv

Conversion tables for iconv (1).

/usr/lib/libp

Profiled libraries.

/usr/lib/locale

Localization databases.

/usr/lib/lp

Line printer subsystem databases and back-end executables.

/usr/lib/mail

Auxiliary programs for the mail(1) subsystem.

/usr/lib/netsvc

Internet network services.

/usr/lib/nfs

Auxiliary NFS-related programs and daemons.

/usr/lib/pics

Position Independent Code (PIC) archives needed to rebuild the run-time linker.

/usr/lib/refer

Auxiliary programs for refer(1).

/usr/lib/sa

Scripts and commands for the system activity report pack-

age. See sar(1).

/usr/lib/saf

Auxiliary programs and daemons related to the service

access facility.

/usr/lib/spell

Auxiliary programs and databases for spell(1). This direc-

tory is only present when the Binary Compatibility Package

is installed.

/usr/lib/uucp

Auxiliary programs and daemons for uucp(1C).

/usr/local

Commands local to a site.

/usr/net/servers

Entry points for foreign name service requests relayed using the network listener. See listen(1M).

/usr/oasys

Commands and files related to the optional Framed Access

Command Environment (FACE) package. See face(1).

/usr/old

Programs that are being phased out.

/usr/openwin

Installation or mount point for the OpenWindows software.

/usr/sadm

System administration files and directories.

/usr/sadm/bin

Binaries for the Form and Menu Language Interpreter

(FMLI) scripts. See fmli(1).

/usr/sadm/install

Executables and scripts for package management.

/usr/sbin

Executables for system administration.

/usr/sbin/static

Statically linked version of selected programs from /usr/bin

and /usr/sbin. These are used to recover from broken

dynamic linking and before all pieces necessary for dynamic linking are present.

/usr/share

Architecture-independent sharable files.

/usr/share/man

On-line reference manual pages (if present).

/usr/share/lib

Architecture-independent databases.

/usr/share/lib/keytables

Keyboard layout description tables.

/usr/share/lib/mailx

Help files for mailx(1).

/usr/share/lib/nterm

nroff(1) terminal tables.

/usr/share/lib/pub

Character set data files.

/usr/share/lib/spell

Auxiliary scripts and databases for spell(1).

/usr/share/lib/tabset

Tab setting escape sequences.

/usr/share/lib/terminfo

Terminal description files for terminfo (4).

/usr/share/lib/tmac

Macro packages and related files for text processing tools, for example, nroff(1) and troff(1).

/usr/share/lib/zoneinfo

Time zone information.

/usr/share/src

Source code for utilities and libraries.

/usr/snadm

SNAG files.

/usr/ucb

Berkeley compatibility package binaries. See Source Compatibility Guide.

/usr/ucbinclude

Berkeley compatibility package headers.

/usr/ucblib

Berkeley compatibility package libraries.

/usr/vmsys

Commands and files related to the optional FACE package.

See face(1). Berkeley compatibility package libraries.

/export File System

A machine with disks may export root file systems, swap files, and /usr file systems to diskless or partially-disked machines that mount them into the standard file system hierarchy. The standard directory tree for sharing these file systems from a server is:

/export

The default root of the exported file system tree.

/export/exec/architecture-name

The exported /usr file system supporting architecture-name for the current release.

/export/exec/architecture-name. release-name
                           The exported /usr file system supporting architecture-name for
                           release-name.

/export/exec/share

The exported common /usr/share directory tree.

/export/exec/share.release-name
                           The exported common /usr/share directory tree for release-
                           name.
/export/root/hostname      The exported root file system for hostname.
/export/swap/hostname      The exported swap file for hostname.
/export/var/hostname       The exported /var directory tree for hostname.

SEE ALSO

at(1), ex (1),face(1), fmli(1), iconv (1),lp(1), mail(1), mailx(1), nroff(1), priocntl(1), refer(1), sar(1), sh(1), spell(1), troff(1), uucp(1C), vi(1), acct(1M), cron (1M), dispadmin(1M), fsck(1M), init(1M), kernel(1M), mknod(1M), mount (1M),useradd(1M), ypbind(1M), mount (2),intro(4), terminfo (4)

Binary Compatibility Guide

Source Compatibility Guide