hier —
layout of file systems
An outline of the file system hierarchy.
Naming is very important. The UNIX System
    relies on filename conventions for much of its power as a system. The
    following file system layout describes generally where things are and what
    they are, with references to other man pages for more detailed
    documentation.
Not all files will be in every system.
  - /
- Root directory of the system.
- /COPYRIGHT
- System copyright notice, most often put on CD-ROM distributions.
- /[a-z]/
- User file systems.
- /altroot/
- Alternate root file system, in case of disaster.
- /bin/
- Utilities used in both single and multi-user environments.
- /boot*
- Second-stage boot loader(s) for some platforms; see
      installboot(8).
- /cdrom/
- Empty directory commonly used by system administrators as a temporary
      mount point for ISO-9660 file systems on CD (or DVD) media.
- /dev/
- Block, character, and other special device files.
    
    
      - MAKEDEV
- Script for creating device files; see
          makedev(8).
- console
- The computer's console device.
- drum
- The computer's swap space device; see
          drum(4).
- fd/
- File descriptor files; see
          fd(4).
- klog
- Kernel logging device; see
          syslog(3).
- kmem
- Kernel virtual memory device; see
          mem(4).
- log
- UNIX domain datagram log socket; see
          syslogd(8).
- mem
- Kernel physical memory device; see
          mem(4).
- null
- The null device; see
          null(4).
- pts/
- Mount point for the pseudo-terminal device file system; see
          mount_ptyfs(8).
- stderr
-  
- stdin
-  
- stdout
- File descriptor files; see
          fd(4).
- tty
- Device pointing to each process's own controlling terminal; see
          tty(4).
- zero
- The zero device; see
          zero(4).
 
- /etc/
- System configuration files and scripts.
    
    
      - amd*
- Configuration files for
          amd(8).
- changelist
- Files backed up by the security script.
- crontab
- Schedule used by the
          cron(8) daemon.
- csh.cshrc
-  
- csh.login
-  
- csh.logout
- System-wide scripts for
          csh(1).
- daily
- Script run each day by
          cron(8).
- daily.conf
- Configuration file for daily; see
          daily.conf(5).
- defaults/
- Default configuration files read by various
          /etc/*.conf files.
- disktab
- Disk description file; see
          disktab(5).
- dm.conf
- Dungeon master configuration; see
          dm.conf(5).
- dumpdates
- Dump history; see
        dump(8).
- exports
- File system export information; see
          mountd(8).
- fstab
- File system mounting table; see
          fstab(5) and
          mount(8).
- ftpusers
- Users denied ftp(1) access;
          see ftpd(8).
- ftpwelcome
- ftp(1) initial message; see
          ftpd(8).
- gettytab
- Terminal configuration database; see
          gettytab(5).
- group
- Group permissions file; see
          group(5).
- hosts
- Host name database backup for
          named(8); see
          hosts(5).
- hosts.equiv
- Trusted machines with equivalent user IDs. (Obsolete.)
- hosts.lpd
- Trusted machines with printing privileges.
- inetd.conf
- Internet server configuration file; see
          inetd(8).
- kerberosV/
- Configuration files for Kerberos version V; see
          kerberos(8).
- localtime
- Local time zone; see
          ctime(3).
- login.conf
- Configuration of user classes and limits; see
          login.conf(5).
- mail/
- Configuration files for
          sendmail(1).
        
        
          - aliases*
- Username alias files.
- sendmail.*
- sendmail(1)
              configuration information.
 
- mail.rc
- System-wide initialization script for
          mail(1).
- man.conf
- Configuration file for
          man(1); see
          man.conf(5).
- master.passwd
- Main password file, readable only by root; see
          passwd(5).
- mk.conf
- Optional file containing
          make(1) variables, used to
          configure pkgsrc and the system sources.
- monthly
- Script run each month by
          cron(8).
- monthly.conf
- Configuration file for monthly; see
          monthly.conf(5).
- motd
- System message of the day.
- mtree/
- mtree(8) configuration
          files.
- named.*
-  
- namedb/
- named(8) configuration
          files and databases.
- netgroup
- Network groups; see
          netgroup(5).
- netstart
- Network startup script .
- networks
- Network name database; see
          networks(5).
- passwd
- World readable password file generated from master.passwd; see
          passwd(5),
          pwd_mkdb(8).
- phones
- Remote host telephone number data base; see
          phones(5).
- printcap
- Printer configuration for
          lpr(1); see
          printcap(5).
- profile
- System-wide scripts for
          sh(1).
- protocols
- Protocol name database; see
          protocols(5).
- pwd.db
- Database form of passwd file; see
          pwd_mkdb(8).
- rc
- Master system startup script invoked by
          init(8); see
          rc(8).
- rc.conf
- Configuration file for system startup and shutdown scripts; see
          rc.conf(5).
- rc.d/
- Directory containing per-subsystem startup and shutdown scripts; see
          rc(8).
- rc.local
- Locally editable system startup script.
- rc.shutdown
- Master system shutdown script invoked by
          shutdown(8); see
          rc(8).
- remote
- Remote host description file; see
          remote(5).
- security
- Daily (in)security script run by
          cron(8).
- security.conf
- Configuration file for security; see
          security.conf(5).
- services
- Service name data base; see
          services(5).
- shells
- List of permitted shells; see
          shells(5).
- skel/
- Sample initialization files for new user accounts.
- sliphome/
- SLIP login/logout scripts; see
          sliplogin(8).
- spwd.db
- Database form of master.passwd file; see
          pwd_mkdb(8).
- syslog.conf
- syslogd(8)
          Configuration file; see
          syslog.conf(5).
- ttyaction
- Login hooks for specific ttys, typically used to chown console
          devices. See
          ttyaction(5).
- ttys
- Terminal initialization information; see
          ttys(5).
- weekly
- Script run each week by
          cron(8).
- weekly.conf
- Configuration file for weekly; see
          weekly.conf(5).
 
- /home/
- Default location for user home directories.
- /kern/
- Mount point for the kern file system; see
      mount_kernfs(8).
- /lib/
- Dynamic linked libraries used by dynamically linked programs that cannot
      rely upon /usr/lib/ being available, such as those
      in /bin/ and /sbin/.
- /libdata/
- Non-executable files (such as device firmware) required at boot time, when
      /usr/libdata may not be available.
- /libexec/
- System utilities (such as the dynamic linker) required by programs and
      libraries that cannot rely upon /usr/libexec/
      being available.
- /mnt/
- Empty directory commonly used by system administrators as a temporary
      mount point.
- /net/
- automounted NFS shares; see
      auto_master(5)
- /netbsd
- Kernel executable image (the operating system loaded into memory at boot
      time).
- /proc/
- Mount point for the process file system; see
      mount_procfs(8).
- /rescue/
- Statically linked rescue tools, for use in system recovery.
- /root/
- Home directory for the super-user.
    
    
      - .cshrc
- Super-user start-up file for
          csh(1).
- .login
- super-user start-up file for
          csh(1).
- .profile
- super-user start-up file for
          sh(1).
- .rhosts
- Super-user id mapping between machines. (Obsolete.)
 
- /sbin/
- System programs and administration utilities used in both single-user and
      multi-user environments.
- /stand/
- Programs used in a standalone environment, that is, things that run on
      bare hardware without a kernel. Currently kernel modules are also placed
      here, although this remains somewhat controversial and they may yet get
      moved.
- /tmp/
- Temporary files. The contents of /tmp are usually
      not preserved across a system reboot.
- /usr/
- Contains the majority of the system utilities and files.
    
    
      - X11R7/
- X11 files (for X11 revision 7).
        
        
          - bin/
- X11 binaries.
- include/
- X11 include files.
- lib/
- X11 libraries.
 
- bin/
- Common utilities, programming tools, and applications.
- games/
- The important stuff.
- include/
- Standard C (and extension) include files.
        
        
          - arpa/
- Include files for Internet service protocols.
- atf/
- Include files for the Automated Testing Framework; see
              atf(7).
- g++/
- Include files for the GNU C++ compiler.
- machine/
- Machine specific include files.
- net/
- Miscellaneous network include files.
- netatalk/
- C include files for AppleTalk protocols see
              atalk(4).
- netinet/
- Include files for Internet standard protocols; see
              inet(4).
- netinet6/
- Include files for Internet protocol version 6; see
              inet6(4).
- netipsec/
- Include files for secret key management, used for security
              protocols; see
              ipsec(4).
- nfs/
- C include files for NFS (Network File System).
- protocols/
- C include files for Berkeley service protocols.
- sys/
- ``System-level'' C include files.
- ufs/
- C include files for several mutually related file systems. (The
              `u' was originally for UNIX.)
 
- lib/
- Archive, profiled, position independent archive, and shared libraries.
        
        
          - lua/
- 
            
              - 5.3/
- Lua 5.3 modules.
 
 
- libdata/
- Miscellaneous utility data files.
- libexec/
- System daemons & system utilities (executed by other programs).
        
      
- mdec/
- Boot blocks, etc.
- obj/
- Architecture-specific target tree produced by building the
          /usr/src tree; often a symbolic link or
          mounted file system.
- pkg/
- Installed third-party software packages.
        
        
          - bin/
- Package binaries.
- include/
- Package include files.
- lib/
- Package libraries.
- libdata/
- Package data files.
- libexec/
- Package daemons.
- sbin/
- Package system utilities.
 
- pkgsrc/
- Build descriptions (packaging) for the NetBSD
          package system.
        
        
          - distfiles/
- Downloaded upstream source archives.
- packages/
- Compiled binary packages.
 There are also several other subdirectories which contain
            packages of a certain category, e.g., archivers, graphics, ... 
- sbin/
- System daemons and system utilities (normally executed by the
          super-user).
- share/
- Architecture-independent files, mostly text.
        
        
          - calendar/
- A variety of calendar files; see
              calendar(1).
- dict/
- Word lists; see
              look(1) and
              spell(1).
            
            
              - words
- Common words.
- web2
- Words from Webster's Second International Dictionary.
- papers/
- Reference databases; see
                  refer(1).
- special/
- Custom word lists; see
                  spell(1).
 
- doc/
- Miscellaneous documentation.
- games/
- Data files used by various games.
- i18n/
- internationalization databases; see
              iconv(3).
- locale/
- Locale databases and gettext message catalogs; see
              setlocale(3) and
              gettext(3).
- man/
- Manual pages.
- me/
- Macros for use with the
              me(7) roff macro
              package.
- misc/
- Miscellaneous system-wide text files.
            
            
              - terminfo
- Terminal characteristics database; see
                  terminfo(5).
- terminfo.cdb
- database form of terminfo file; see
                  tic(1).
 
- mk/
- Include files for
              make(1).
- ms/
- Macros for use with the
              ms(7) roff macro
              package.
- nls/
- Message catalogs; see
              catgets(3).
- tmac/
- Text processing macros; see
              nroff(1) and
              troff(1).
- zoneinfo/
- Time zone database; see
              tzfile(5).
 
- tests/
- Test programs; see
          tests(7) for information
          on how to run them.
 
- /usr/src/
- NetBSD and local source files.
    
    
      - bin/
- Source for utilities/files in /bin.
- common/
- Sources shared between kernel and userland.
- crypto/
- Cryptographic source, which may have import or export
        restrictions.
- dist/
- Third-party ‘virgin’ source code, referenced by other
          parts of the source tree. (Deprecated; use
          external/ instead.)
- distrib/
- Tools and data files for making NetBSD
          releases and distributions.
- doc/
- Documentation about the source tree (i.e., about the tree, not about
          how to use the software in the tree.)
- etc/
- Source (usually example files) for files in
          /etc.
- external/
- Source for programs from external third parties (where
          NetBSD is the not the primary maintainer),
          grouped by license, and then products per license.
        
        
          - apache2/
- Apache 2.0 license.
- bsd/
- BSD (or equivalent) licensed software, possibly with the
              “advertising clause”.
- cddl/
- Common Development and Distribution License (the Sun license which
              is based on the Mozilla Public License version 1.1).
- gpl2/
- GNU Public License, version 2 (or earlier).
- gpl3/
- GNU Public License, version 3.
- historical/
- Lucent's old license.
- ibm-public/
- IBM's public license.
- intel-fw-eula/
- Intel firmware license with redistribution restricted to OEM.
- intel-fw-public/
- Intel firmware license permitting redistribution with terms
              similar to BSD licensed software.
- intel-public/
- Intel license permitting redistribution with terms similar to BSD
              licensed software.
- mit/
- MIT (X11) style license.
- zlib/
- BSD-like zlib license.
 
- games/
- Source for utilities/files in /usr/games.
- gnu/
- Source for programs covered by the GNU license (or similar)
          (deprecated; use external/gpl2/ or
          external/gpl3/ as appropriate).
- include/
- Source for files in /usr/include.
- lib/
- Source for libraries in /usr/lib.
- libexec/
- Source for utilities/files in
        /usr/libexec.
- regress/
- Various legacy regression tests.
- rescue/
- Source/makefiles for /rescue.
- sbin/
- Source for utilities/files in /sbin.
- share/
- Source for files in /usr/share.
        
        
          - doc/
- 
            
            
              - papers/
- Source for various historical technical papers (many from
                  Berkeley).
- psd/
- Source for Programmer's Supplementary Documents.
- smm/
- Source for System Manager's Manual.
- usd/
- Source for User's Supplementary Documents.
 
 
- sys/
- Kernel source files.
        
        
          - arch/
- Architecture-specific support.
            
            
              - acorn32/
- Acorn RiscPC/A7000 and VLSI RC7500.
- algor/
- Algorithmics Ltd. MIPS evaluations boards.
- alpha/
- Digital/Compaq Alpha.
- amd64/
- Computers with x86_64 capable CPUs.
- amiga/
- Commodore Amiga and MacroSystem DraCo.
- amigappc/
- PowerPC based Amiga boards.
- arc/
- MIPS-based machines following the Advanced RISC Computing
                  spec.
- arm/
- ARM processor general support.
- atari/
- Atari TT030, Falcon and Hades.
- bebox/
- Be Inc. BeBox.
- cats/
- Chalice Technology's CATS and Intel's EBSA-285 evaluation
                  boards.
- cesfic/
- CES FIC8234 VME processor board.
- cobalt/
- Cobalt Networks' MIPS-based Microserver.
- dreamcast/
- Sega Dreamcast game console.
- emips/
- Machines based on Extensible MIPS.
- evbarm/
- ARM based evaluation boards.
- evbmips/
- MIPS based evaluation boards.
- evbppc/
- PowerPC based evaluation boards and appliances.
- evbsh3/
- SH3/SH4 based evaluation boards.
- ews4800mips/
- NEC's MIPS based EWS4800 workstations.
- hp300/
- Hewlett-Packard 9000/300 and 400 680x0-based
                workstations.
- hppa/
- Hewlett-Packard 9000/700 and 9000/800 HPPA based
                workstations.
- hpcarm/
- StrongARM based WinCE PDA machines.
- hpcmips/
- MIPS based WinCE PDA machines.
- hpcsh/
- Hitachi SH3/4 based WinCE PDA machines.
- hppa/
- HPPA processor general support.
- i386/
- 32-bit 80x86-based IBM PCs and clones.
- ibmnws/
- IBM Network Station 1000.
- iyonix/
- Castle Technology's Iyonix ARM based PCs.
- luna68k/
- Omron Tateishi Electric's 680x0-based LUNA workstations.
- m68k/
- 680x0 processor general support.
- mac68k/
- Apple Macintosh with 68k CPU.
- macppc/
- Apple Power Macintosh and clones.
- mips/
- MIPS processor general support.
- mipsco/
- MIPS Computer Systems Inc. family of workstations and
                servers.
- mmeye/
- Brains Inc. SH3 based mmEye multimedia server.
- mvme68k/
- Motorola MVME 680x0-based SBCs.
- mvmeppc/
- Motorola PowerPC VME SBCs.
- netwinder/
- StrongARM based NetWinder machines.
- news68k/
- Sony's 680x0-based NEWS workstations.
- newsmips/
- Sony's MIPS-based NEWS workstations.
- next68k/
- NeXT 68k "black" hardware.
- ofppc/
- Open Firmware PowerPC workstations.
- playstation2/
- SONY PlayStation 2.
- pmax/
- Digital MIPS-based DECstations and DECsystems.
- powerpc/
- PowerPC processor general support.
- prep/
- PReP (PowerPC Reference Platform) and CHRP (Common Hardware
                  Reference Platform) machines.
- sandpoint/
- Motorola Sandpoint reference platform.
- sbmips/
- Broadcom/SiByte evaluation boards.
- sgimips/
- Silicon Graphics' MIPS-based workstations.
- sh3/
- SH3/SH4 processor general support.
- shark/
- Digital DNARD ("Shark").
- sparc/
- Sun Microsystems SPARC (32-bit) and UltraSPARC (in 32-bit
                  mode).
- sparc64/
- Sun Microsystems UltraSPARC (in native 64-bit mode).
- sun2/
- Sun Microsystems 68010-based Sun 2 architecture.
- sun3/
- Sun Microsystems 68020/68030-based Sun 3/3x architecture.
- sun68k/
- 680x0-based Sun architecture general support.
- vax/
- Digital VAX.
- x68k/
- Sharp X680x0 680x0-based workstations.
- x86/
- General support for PC/AT compatibles with ia32 or x86_64
                  CPUs.
- xen/
- The Xen virtual machine monitor.
- zaurus/
- Sharp C3x00 Arm based PDA.
 
- compat/
- Kernel compatibility modules directory.
            
            
              - common/
- Common compatibility routines, old
                  4BSD and
                  NetBSD routines.
- freebsd/
- Support for FreeBSD binaries; see
                  compat_freebsd(8).
- hpux/
- Support for 68000 HP-UX binaries.
- linux/
- Support for Linux binaries; see
                  compat_linux(8).
- m68k4k/
- Support for 4KB page 68000 binaries.
- netbsd32/
- Support for NetBSD 32-bit binaries on
                  64 bit platforms with compatible CPU families.
- ossaudio/
- Support for OSS audio.
- sunos/
- Support for SunOS 4.x binaries; see
                  compat_sunos(8).
- ultrix/
- Support for ULTRIX binaries.
- vax1k/
- Support for older VAX binaries that started on a 1 KB
                  boundary.
 
- conf/
- Architecture independent configuration directory.
- crypto/
- Cryptographic kernel source, which may have import or export
              restrictions.
- ddb/
- In-kernel debugger.
- dev/
- Architecture independent device support.
- fs/
- File systems. See also ufs/ and
              miscfs/.
            
              - adosfs/
- AmigaDOS file-system support; see
                  mount_ados(8).
- cd9660/
- Support for the ISO-9660 file system; see
                  mount_cd9660(8).
- filecorefs/
- Support for the Acorn RISC OS filecore file system; see
                  mount_filecore(8).
- msdosfs/
- MS-DOS file system; see
                  mount_msdos(8).
- ntfs/
- NTFS file system support; see
                  mount_ntfs(8).
- ptyfs/
- Pseudo-terminal device file system; see
                  mount_ptyfs(8).
- smbfs/
- SMB/CIFS file system support; see
                  mount_smbfs(8).
- union/
- Union file system; see
                  mount_union(8).
 
- gdbscripts/
- Support for accessing kernel structures from within the debugger
              gdb(1).
            
          
- kern/
- Primary kernel source code.
- lib/
- Libraries supporting the kernel.
            
            
              - libkern/
- C library routines used in the kernel.
- libsa/
- Machine-independent standalone library, used by boot
                loaders.
- libz/
- Compression library.
 
- miscfs/
- More file systems.
            
            
              - deadfs/
- Kernel only dead file system.
- fdesc/
- File descriptor file system; see
                  mount_fdesc(8).
- fifofs/
- POSIX FIFO (named pipe) support.
- genfs/
- Generic file system code that supports other file
                systems.
- kernfs/
- Kernel namespace file system; see
                  mount_kernfs(8).
- nullfs/
- Loop back file system; see
                  mount_null(8).
- overlay/
- Overlay file system; see
                  mount_overlay(8).
- procfs/
- Process file system; see
                  mount_procfs(8).
- specfs/
- Support for block and character special files.
- syncfs/
- Kernel trickle sync algorithm.
- umapfs/
- User and group re-mapping file system; see
                  mount_umap(8).
 
- net/
- Miscellaneous networking support.
- netatalk/
- AppleTalk networking support.
- netinet/
- IP networking support.
- netinet6/
- IPv6 networking support.
- netipsec/
- Key database for IPsec networking support.
- nfs/
- NFS (network file system) support, both client and server.
- stand/
- Kernel standalone support.
- sys/
- Kernel (and system) include files.
- ufs/
- Still more file systems.
            
            
              - chfs/
- A FFS-based file system for use on raw flash.
- ext2fs/
- The Linux ext2 file system.
- ffs/
- The Berkeley Fast File System.
- lfs/
- The Berkeley log-structured file system.
- mfs/
- The in-memory file system.
- ufs/
- Shared UNIX file system support.
 
- uvm/
- UVM virtual memory system.
 
- tests/
- Source for test programs in /usr/tests.
- usr.bin/
- Source for utilities/files in /usr/bin.
- usr.sbin/
- Source for utilities/files in /usr/sbin.
 
- /var/
- Multi-purpose log, temporary, transient, and spool files.
    
    
      - account/
- System accounting files.
        
        
          - acct
- Execution accounting file; see
              acct(5).
 
- at/
- Timed command scheduling files; see
          at(1).
- backups/
- Miscellaneous backup files, largely of files found in
          /etc.
- chroot/
- Home directories of applications which are run in a
          chroot(8)
          “cage”.
- crash/
- System (kernel) crash dumps; see
          savecore(8).
- cron/
- Scheduled commands configuration files; see
          cron(8) and
          crontab(5).
- db/
- Miscellaneous automatically generated system-specific database files,
          and persistent files used in the maintenance of third party software.
        
        
          - pkg
- Default location for metadata related to third party software
              packages. See
              pkg_add(1) for more
              details of the NetBSD Packages Collection,
              or pkgsrc.
 
- games/
- Miscellaneous game status, log, and high score files.
- heimdal/
- Kerberos 5 KDC database; see
          kdc(8).
- log/
- Miscellaneous system log files.
        
        
          - amd.*
- amd(8) logs.
- daily.out
- Output of the last run of the /etc/daily
              script.
- ftp.*
- ftp(1) logs.
- kerberos.*
- kerberos(8)
            logs.
- lastlog
- System last-time-logged-in database; see
              utmp(5).
- lpd-errs.*
- Printer daemon error logs; see
              lpd(8).
- maillog.*
- sendmail(1) and
              postfix(1) (and
              other mail-related) log files.
- messages.*
- General system information log.
- monthly.out
- Output of the last run of the /etc/monthly
              script.
- secure
- Sensitive security information log.
- sendmail.st
- sendmail(1)
              statistics.
- timed.*
- timed(8) logs.
- weekly.out
- Output of the last run of the /etc/weekly
              script.
- wtmp
- Login and logout log; see
              utmp(5).
- wtmpx
- Another login and logout log; see
              utmpx(5).
 
- mail/
- User e-mail inboxes.
- msgs/
- System messages; see
          msgs(1).
- preserve/
- Temporary home of files preserved after an accidental death of
          ex(1) or
          vi(1).
- quotas/
- File system quota information. (Legacy.)
- run/
- System information files, rebuilt after each reboot.
        
        
          - dmesg.boot
- A dump from dmesg(8)
              taken at boot time.
- utmp
- Database of currently logged in users; see
              utmp(5).
- utmpx
- Another database of currently logged in users; see
              utmpx(5).
 
- rwho/
- Rwho data files; see
          rwhod(8),
          rwho(1), and
          ruptime(1).
- spool/
- Miscellaneous printer and mail system spooling directories.
        
        
          - ftp/
- Commonly “~ftp”, the anonymous ftp root directory;
              see ftpd(8).
- mqueue/
- Sendmail mail queue; see
              sendmail(1).
- news/
- Network news archival and spooling directories.
- output/
- Printer spooling directories.
- postfix/
- Postfix mail queue; see
              postfix(1).
 
- tmp/
- Temporary files that are not discarded between system reboots.
        
        
          - vi.recover/
- Recovery directory for new (current)
              vi(1).
 
- yp/
- Databases and configuration for the NIS (YP) system; see
          nis(8).
 
Ahier manual page appeared in
  Version 7 AT&T UNIX.