A Digital UNIX Standard Directory Structure

Digital recommends that you install products in the /opt, /usr/opt, and /var/opt directories. As part of installation, the subset control program that you provide creates links from these directories to directories that would typically be in the users' search paths. Most Digital UNIX systems use the standard directory structure shown in this appendix. Placing your product within this standard directory structure can help to ensure that your product installs successfully on most customer systems.

Figure A-1 and Figure A-2 show the directories in the Digital UNIX standard directory structure. These are the directories that you should use to ensure that your product is portable to other systems. (Some of the illustrated directories are actually symbolic links.)

Figure A-1: Base System Directory Structure

Table A-1 describes the contents and purpose of the directories shown in Figure A-1.

Table A-1: Contents and Purpose of Base System Directories
Directory	Description
`/`	The root directory of the file system
`/dev/`	Block and character device special files
`/etc/`	System configuration files and databases; nonexecutable files
`nls/`	National language support databases
`/lost+found/`	Files located by `fsck`
`/opt/`	Optional for layered products, such as applications and device drivers
`/sbin/`	Commands essential to boot the system (most of these commands depend on shared libraries or the loader and have other versions in `/usr/bin` or `/usr/sbin`)
`init.d/`	System state rc files
`rc0.d/`	The rc files executed for system-state 0
`rc2.d/`	The rc files executed for system-state 2
`rc3.d/`	The rc files executed for system-state 3
`/subsys/`	Dynamically configured kernel modules required in single-user mode
`/tmp/`	System-generated temporary files, usually not preserved across a system reboot.
`/usr/`	Most user utilities and applications
`bin/`	Common utilities and applications
`ccs/`	C compilation system; tools and libraries used to generate C programs
`bin/`	Development binaries such as `cc`, `ld`, and `make`
`lib/`	Development libraries and back ends
`include/`	Program header (include) files; not all subdirectories are listed in this appendix
`mach/`	Mach-specific C include files
`machine/`	Machine-specific C include files
`net/`	Miscellaneous network C include files
`netinet/`	C include files for Internet standard protocols
`netns/`	C include files for XNS standard protocols
`nfs/`	C include files for Network File System
`protocols/`	C include files for Berkeley service protocols
`rpc/`	C include files for remote procedure calls
`servers/`	C include files for servers
`sys/`	System C include files (kernel data structures)
`tli/`	C include files for Transport Layer Interface
`ufs/`	C include files for UNIX File System
`examples/`	Subdirectories of programming examples
`lbin/`	Back-end executable files
`spell/`	Spell back-end
`uucp/`	UNIX-to-UNIX Copy (UUCP) programs
`lib/`	Links to libraries located elsewhere (`/usr/ccs/lib`), (`/usr/libin`), (`/usr/share/lib`), (`/X11/lib`); included for compatibility
`opt/`	Optional layered products, such as applications and device drivers
`sbin/`	System administration utilities and system utilities
`share/`	Architecture-independent ASCII text files
`dict/`	Word lists
`lib/`	Various libraries
`me/`	Macros for use with the `me` macro package
`ms/`	Macros for use with the `ms` macro package
`tabset/`	Tab description files for a variety of terminals; used in `/etc/termcap`
`terminfo/`	Terminal information database
`tmac/`	Text-processing macros
`man/`	Online reference pages
`man1/`	Source for user command reference pages
`man2/`	Source for system call reference pages
`man3/`	Source for library routine reference pages
`man4/`	Source for file format reference pages
`man5/`	Source for miscellaneous reference pages
`man7/`	Source for device reference pages
`man8/`	Source for administrator command reference pages
`cat1-cat8`	Formatted versions of files in `man1` - `man8`
`shlib/`	Binary-loadable shared libraries; shared versions of libraries in `/usr/ccs/lib`
`sys/`	System configuration files
`BINARY`	Object files
`conf/`	Kernel configuration control files
`include/`	Header files
`/var/`	Multipurpose log, temporary, varying, and spool files
`adm/`	Common administrative files and databases
`crash/`	For saving kernel crash dumps
`cron/`	Files used by `cron`
`sendmail/`	Configuration and database files for `sendmail`
`syslog/`	Files generated by `syslog`
`opt/`	Optional layered products, such as applications and device drivers
`run/`	Files created when daemons are running
`spool/`	Miscellaneous printer and mail-system spooling directories
`lpd/`	Line printer spooling directories
`mail/`	Incoming mail messages
`mqueue/`	Undelivered mail queue
`uucp/`	UUCP spool directory
`subsys/`	Loadable kernel modules required in multiuser mode
`tmp/`	Application-generated temporary files that are kept between system reboots
`/vmunix`	Pure kernel executable (the operating system loaded into memory at boot time)

Figure A-2: X Directory Structure

Table A-2 describes the contents and purpose of the directories shown in Figure A-2.

Table A-2: Contents and Purpose of X Directories
Directory	Description
`/usr/`	Most user utilities and applications
`bin/`	Common utilities and applications
`X11/`	X applications
`demos/`	Miscellaneous demo programs
`examples/`	Example programs
`dxpaint/`	Sample Paint image
`motif/`	Motif example programs
`include/`	Header files
`DPS/`	Files for DPS
`DXm/`	Files for libDXm
`Mrm/`	Files for libMrm
`uil/`	UIL header files
`X11/`	X C header files
`bitmaps/`	X bitmaps
`extensions/`	Header files for use with X extensions
`Xaw/`	Files for libXaw
`Xserver/`	Header files used for loadable X server libraries
`Xm/`	Header files for libXm
`lib/`	Static archive X libraries
`cda/`	CDA style guides
`dxbook/`	Default Bookreader bookshelf
`emacs/`	Emacs directory base
`X11`
`app-defaults/`	System-wide resource files for X client applications
`bitmaps/`	Program-specific bitmaps
`appdata/`	Generic program-specific data
`config/`	Imake configuration files
`DPS/`	Display Postscript files
`fonts/`	Font files
`100dpi/`	100 dpi fonts from X Consortium
`75dpi/`	75 dpi fonts from X Consortium
`decwin/`	DECwindows fonts
`100dpi/`	100 dpi fonts
`75dpi/`	75 dpi fonts
`misc/`	Fonts from X Consortium
`Speedo/`	Speedo scalable fonts
`Type1/`	Type1 scalable fonts
`Type1Adobe/`	Adobe Type1 scalable fonts
`afm/`	Adobe font metrics
`user`	Fonts from layered products and local installations
`100dpi/`	100 dpi fonts
`75dpi/`	75 dpi fonts
`misc/`	Other fonts
`fs/`	Fontserver config and error log files
`help/`	Help files for X client applications; subdirectories as applicable
`keymaps/`	Keymaps for various keyboards
`twm/`	Default configuration for `twm` window manager
`uid/`	User Interface Definitions for X client applications
`x11perfcomp/`	Scripts for analyzing `x11perf` output
`xdm/`	X Display Manager configuration and resource files, and error log
`shlib/`	Shareable libraries
`X11/`	Shareable libraries loaded by X server