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28 .\" @(#)hier.7 8.1 (Berkeley) 6/5/93
36 .Nd layout of file systems
38 A sketch of the file system hierarchy.
39 .Bl -tag -width "/libexec/"
41 root directory of the file system
43 user utilities fundamental to both single-user and multi-user environments
45 programs and configuration files used during operating system bootstrap
47 .Bl -tag -width "defaults/" -compact
49 default bootstrapping configuration files; see
52 Compiled flattened device tree (FDT) files; see
57 Mount point for EFI System Partition (ESP) on UEFI systems
59 loadable kernel modules containing binary firmware for hardware that needs
60 firmware downloaded to it to function
62 pure kernel executable (the operating system loaded into memory
63 at boot time) and kernel modules
65 third-party loadable kernel modules, such as the ones installed from
68 Compiled flattened device tree (FDT) overlays; see
77 default mount point for CD-ROM drives
85 device special files managed by
88 .Bl -tag -width "defaults/" -compact
90 file descriptor files;
95 system configuration files and scripts
97 .Bl -tag -width "defaults/" -compact
99 default system configuration files;
103 bluetooth configuration files
105 local timezone information;
109 Sendmail control files
111 mtree configuration files;
115 configuration files for the Pluggable Authentication Modules (PAM)
118 scripts that are run daily, weekly, and monthly, via
123 system and daemon startup/control scripts;
127 OpenBSM audit configuration files;
131 ppp configuration files;
135 OpenSSH configuration files;
139 OpenSSL configuration files
142 critical system libraries needed for binaries in
147 .Bl -tag -width "defaults/" -compact
151 Capsicum support libraries
153 class-specific libraries for the
157 vendor-specific libraries to extend the
162 critical system utilities needed for binaries in
167 contains subdirectories to be used as mount points
168 for removable media such as CDs, USB drives, and
171 empty directory commonly used by
172 system administrators as a temporary mount point
174 automounted NFS shares;
178 a non-existent directory;
179 by convention, it serves as a home directory
180 for special user accounts
181 that need no home directory;
189 statically linked programs for emergency recovery;
193 root's HOME directory
195 system programs and administration utilities
196 fundamental to both single-user and multi-user environments
198 temporary files that are not guaranteed to persist across system reboots
200 contains the majority of user utilities and applications
202 .Bl -tag -width "freebsd-dist/" -compact
204 common utilities, programming tools, and applications
206 files needed to support binary compatibility with other operating systems;
217 standard C include files
219 .Bl -tag -width "kerberos5/" -compact
221 C include files for Internet service protocols
223 C include files for the SNMP daemon
227 C include files for the Common Access Methods Layer
228 .Bl -tag -width "kerberos5/" -compact
230 SCSI device on top of CAM
233 C include files for programming various
236 .Bl -tag -width "kerberos5/" -compact
238 various header files describing driver- and bus-independent
241 Open Firmware support
254 .Bl -tag -width "kerberos5/" -compact
256 per-process file descriptors file system
260 C include files for NFS (Network File System) version 2, 3 and 4
274 .Bl -tag -width "kerberos5/" -compact
289 C include files for libmilter,
294 machine-specific C include files
296 miscellaneous network C include files
297 .Bl -tag -width Fl -compact
299 C include files for alternate packet queueing; see
303 C include files for 802.11 wireless networking;
307 C include files for Internet standard protocols;
311 C include files for Internet protocol version 6;
315 kernel key-management service;
321 C include files for NFS (Network File System) version 2 and 3 (legacy)
323 OpenSSL (Cryptography/SSL toolkit) headers
325 C include files for Berkeley service protocols
327 remote procedure calls;
331 definition of RPC service structures; see
337 system C include files (kernel data structures)
342 .\" .Bl -tag -width "kerberos5/" -compact
349 C include files for UFS (The U-word File System)
350 .Bl -tag -width "kerberos5/" -compact
367 .Bl -tag -width Fl -compact
369 shared libraries for compatibility
371 standalone debug data for the kernel and base system libraries and binaries
373 DTrace library scripts
375 OpenSSL (Cryptography/SSL toolkit) dynamically loadable engines
379 miscellaneous utility data files
381 .Bl -tag -width Fl -compact
394 system daemons & system utilities (executed by other programs)
396 .Bl -tag -width Fl -compact
398 utilities to manipulate a.out executables
400 utilities to manipulate ELF executables
402 utilities and filters for LP print system;
419 local executables, libraries, etc.
420 Also used as the default destination for the
425 the general layout sketched out by
433 .Pa share/doc/<port>/ Ns Pc ,
439 architecture-specific target tree produced by building
446 ports collection; see
449 system daemons & system utilities (executed by users)
451 architecture-independent files
453 .Bl -tag -width Fl -compact
455 a variety of pre-fab calendar files;
462 .Bl -tag -width Fl -compact
465 terms, proper names, and jargon
467 words from Webster's 2nd International
470 miscellaneous documentation;
471 source for most of the printed
477 .Bl -tag -width Fl -compact
479 Frequently Asked Questions
481 implementation notes for IPv6
483 Spanish translations of documents in /usr/share/doc
488 Japanese translations of documents in /usr/share/doc
490 License files for vendor supplied firmware files
492 HTML documents pertaining to ncurses;
496 HTML documents pertaining to the Network Time Protocol
498 Russian translations of documents in /usr/share/doc
503 Chinese translations of documents in /usr/share/doc
506 various examples for users and programmers
508 firmware images loaded by userland programs
510 ASCII text files used by various games
512 known trusted and revoked keys
513 .Bl -tag -width Fl -compact
527 miscellaneous system-wide ASCII text files
528 .Bl -tag -width Fl -compact
532 terminal characteristics database;
541 national language support files
543 data files for security policies such as
551 (dot) files for new accounts
553 MIBs, example files and tree definitions for the SNMP daemon
554 .Bl -tag -width Fl -compact
556 tree definition files for use with
562 files used by syscons;
565 .Bl -tag -width Fl -compact
573 console keyboard maps;
582 files necessary for the -sysroot compiler/linker argument to build non-native
584 .Bl -tag -width Fl -compact
594 .Bl -tag -width Fl -compact
595 .It Pa MACHINE.MACHINE_ARCH/
596 represent the binary ABI for these files.
608 tab description files for a variety of terminals; used in
613 localization support and utilities for
619 .Bl -tag -width Fl -compact
627 console keyboard maps;
633 .\" console screen maps
636 timezone configuration information;
646 .Bl -tag -width "kerberos5/" -compact
648 source code for files in /bin
650 utilities covered by the Common Development and Distribution License
652 source code for contributed software
654 source code for contributed cryptography software
656 source code for files in
659 utilities covered by the GNU General Public License
661 source code for files in
664 build infrastructure for Kerberos version 5
666 source code for files in
671 source code for files in
674 files required to produce a
678 source code for files in
681 source code for files in
684 build directory for files in
690 boot loader source code
693 .Bl -tag -width Fl -compact
695 AMD64 architecture support
697 ARM architecture support
699 ARMv8 architecture support
705 CDDL-licensed optional sources, including ZFS
716 i386 (32 bit) architecture support
718 main part of the kernel
736 PowerPC/POWER architecture support
738 RISC-V architecture support
748 code shared by AMD64 and i386 architectures
751 support for experimental DIRDEPS_BUILD
753 source code for files in
756 tools used for maintenance and testing of
759 source code for files in
762 source code for files in
773 multi-purpose log, temporary, transient, and spool files
775 .Bl -tag -width "defaults/" -compact
777 system accounting files
779 .Bl -tag -width Fl -compact
781 execution accounting file;
787 timed command scheduling files;
791 .Bl -tag -width Fl -compact
793 directory containing job files
795 directory containing output spool files
799 miscellaneous backup files
801 miscellaneous cached files
803 .Bl -tag -width Fl -compact
810 default directory to store kernel crash dumps; see
819 .Bl -tag -width Fl -compact
827 miscellaneous automatically generated system-specific database files
828 .Bl -tag -width Fl -compact
829 .It Pa freebsd-update/
831 work directory for temporary files and downloaded updates
834 empty directory for use by programs that need a specifically empty directory.
837 for privilege separation
839 miscellaneous game status and score files
841 Kerberos server databases; see
844 miscellaneous system log files
846 .Bl -tag -width Fl -compact
860 system messages database;
864 temporary home of files preserved after an accidental death
869 file system quota information files
871 system information files describing various info about
872 system since it was booted
874 .Bl -tag -width Fl -compact
878 .Xr unix 4 Ns -domain sockets
882 group for command connection sockets; see
885 database of current users;
898 miscellaneous printer and mail system spooling directories
900 .Bl -tag -width Fl -compact
902 undelivered submission mail queue;
910 undelivered mail queue;
914 line printer spooling directories
918 temporary files that are kept between system reboots
920 .Bl -tag -width Fl -compact
922 the directory where recovery files are stored
931 This manual page documents the default
933 file system layout, but
934 the actual hierarchy on a given system is defined at the system
935 administrator's discretion.
936 A well-maintained installation will include a customized version of
948 manual page appeared in