HIER(7)

NAME
hier - layout of file systems

DESCRIPTION
A sketch of the file system hierarchy.

/   root directory of the file system

/bin/
    user utilities fundamental to both single-user and multi-user environments

/boot/
    programs and configuration files used during operating system bootstrap

    defaults/
        default bootstrapping configuration files; see loader.conf(5)
    dtb/
        Compiled flattened device tree (FDT) files; see fdt(4) and dtc(1)
    efi/
        Mount point for EFI System Partition (ESP) on UEFI systems
    firmware/
        loadable kernel modules containing binary firmware for hardware that needs firmware downloaded to it to function
    kernel/
        pure kernel executable (the operating system loaded into memory at boot time) and kernel modules
    modules/
        third-party loadable kernel modules, such as the ones installed from ports(7)
    overlays/
        Compiled flattened device tree (FDT) overlays; see fdt(4) and dtc(1)
    zfs/
        zfs(8) zpool cache files

/cdrom/
    default mount point for CD-ROM drives

/compat/
    normally a link to /usr/compat. If not, then the /usr/compat comments apply

/dev/
    device special files managed by devfs(5)

    fd/ file descriptor files; see fd(4)

/etc/
    system configuration files and scripts

    defaults/
        default system configuration files; see rc(8)
    bluetooth/
        bluetooth configuration files
    localtime
        local timezone information; see ctime(3)
    mail/
        Sendmail control files
    mtree/
        mtree configuration files; see mtree(8)
    pam.d/
        configuration files for the Pluggable Authentication Modules (PAM) library
    periodic/
        scripts that are run daily, weekly, and monthly, via cron(8); see periodic(8)
    rc.d/
        system and daemon startup/control scripts; see rc(8)
    security/
        OpenBSM audit configuration files; see audit(8)
    ppp/
        ppp configuration files; see ppp(8)
    ssh/
        OpenSSH configuration files; see ssh(1)
    ssl/
        OpenSSL configuration files

/lib/
    critical system libraries needed for binaries in /bin and /sbin

    casper/
        service-specific libcasper(3) Capsicum support libraries
    geom/
        class-specific libraries for the geom(8) utility
    nvmecontrol/
        vendor-specific libraries to extend the nvmecontrol(8) utility

/libexec/
    critical system utilities needed for binaries in /bin and /sbin

/media/
    contains subdirectories to be used as mount points for removable media such as CDs, USB drives, and floppy disks

/mnt/
    empty directory commonly used by system administrators as a temporary mount point

/net/
    automounted NFS shares; see auto_master(5)

/proc/
    process file system; see procfs(5)

/rescue/
    statically linked programs for emergency recovery; see rescue(8)

/root/
    root's HOME directory

/sbin/
    system programs and administration utilities fundamental to both single-user and multi-user environments

/tmp/
    temporary files that are not guaranteed to persist across system reboots

/usr/
    contains the majority of user utilities and applications

    bin/
        common utilities, programming tools, and applications
    compat/
        files needed to support binary compatibility with other operating systems; see linux(4)
    include/
        standard C include files

        arpa/
            C include files for Internet service protocols
        bsnmp/
            C include files for the SNMP daemon
        c++/
            C++ include files
        cam/
            C include files for the Common Access Methods Layer
            scsi/
                SCSI device on top of CAM
        dev/
            C include files for programming various FreeBSD devices
            ic/ various header files describing driver- and bus-independent hardware circuits
            ofw/
                Open Firmware support
            pbio/
                8255 PPI cards; see pbio(4)
            ppbus/
                parallel port bus; see ppbus(4)
            usb/
                USB subsystem
        fs/
            fdescfs/
                per-process file descriptors file system
            msdosfs/
                MS-DOS file system
            nfs/
                C include files for NFS (Network File System) version 2, 3 and 4
            nullfs/
                loopback file system
            procfs/
                process file system
            smbfs/
                SMB/CIFS file system
            udf/
                UDF file system
            unionfs
                union file system
        geom/
            GEOM framework
            concat/
                CONCAT GEOM class
            gate/
                GATE GEOM class
            mirror/
                MIRROR GEOM class
            nop/
                NOP GEOM class
            raid3/
                RAID3 GEOM class
            stripe/
                STRIPE GEOM class
        libmilter/
            C include files for libmilter, the sendmail(8) mail filter API
        machine/
            machine-specific C include files
        net/
            miscellaneous network C include files
            altq/
                C include files for alternate packet queueing; see altq(4)
        net80211/
            C include files for 802.11 wireless networking; see net80211(4)
        netinet/
            C include files for Internet standard protocols; see inet(4)
        netinet6/
            C include files for Internet protocol version 6; see inet6(4)
        netipsec/
            kernel key-management service; see ipsec(4)
        netsmb/
            SMB/CIFS requester
        nfs/
            C include files for NFS (Network File System) version 2 and 3 (legacy)
        openssl/
            OpenSSL (Cryptography/SSL toolkit) headers
        protocols/
            C include files for Berkeley service protocols
        rpc/
            remote procedure calls; see rpc(3)
        rpcsvc/
            definition of RPC service structures; see rpc(3)
        security/
            PAM; see pam(8)
        sys/
            system C include files (kernel data structures)
        ufs/
            C include files for UFS (The U-word File System)
            ffs/
                Fast file system
            ufs/
                UFS file system
        vm/ virtual memory; see vmstat(8)

    lib/
        shared and archive ar(1)-type libraries

        aout/
            a.out archive libraries
        compat/
            shared libraries for compatibility
            aout/
                a.out backward compatibility libraries
        debug/
            standalone debug data for the kernel and base system libraries and binaries
        dtrace/
            DTrace library scripts
        engines/
            OpenSSL (Cryptography/SSL toolkit) dynamically loadable engines

    libdata/
        miscellaneous utility data files

        gcc/
            gcc(1) configuration data
        ldscripts/
            linker scripts; see ld(1)

    libexec/
        system daemons & system utilities (executed by other programs)

        aout/
            utilities to manipulate a.out executables
        elf/
            utilities to manipulate ELF executables
        lpr/
            utilities and filters for LP print system; see lpr(1)
        sendmail/
            the sendmail(8) binary; see mailwrapper(8)
        sm.bin/
            restricted shell for sendmail(8); see smrsh(8)

    local/
        local executables, libraries, etc. Also used as the default destination for the ports(7) framework. Within local/, the general layout sketched out by hier for /usr should be used. Exceptions are the ports documentation (in share/doc/<port>/), and /usr/local/etc (mimics /etc).
    obj/
        architecture-specific target tree produced by building the /usr/src tree
    ports/
        FreeBSD ports collection; see ports(7)
    sbin/
        system daemons & system utilities (executed by users)
    share/
        architecture-independent files

        calendar/
            a variety of pre-fab calendar files; see calendar(1)
        dict/
            word lists; see look(1)
            freebsd
                FreeBSD-specific terms, proper names, and jargon
            web2
                words from Webster's 2nd International
        doc/
            miscellaneous documentation; source for most of the printed BSD manuals (available from the USENIX association)
            FAQ/
                Frequently Asked Questions
            IPv6/
                implementation notes for IPv6
            es/ Spanish translations of documents in /usr/share/doc
            handbook/
                FreeBSD Handbook
            ja/ Japanese translations of documents in /usr/share/doc
            legal/
                License files for vendor supplied firmware files
            ncurses/
                HTML documents pertaining to ncurses; see ncurses(3)
            ntp/
                HTML documents pertaining to the Network Time Protocol
            ru/ Russian translations of documents in /usr/share/doc
            tutorials/
                FreeBSD tutorials
            zh/ Chinese translations of documents in /usr/share/doc
        examples/
            various examples for users and programmers
        firmware/
            firmware images loaded by userland programs
        games/
            ASCII text files used by various games
        keys/
            known trusted and revoked keys
            pkg/
                fingerprints for pkg(7) and pkg(8)
        locale/
            localization files; see setlocale(3)
        man/
            manual pages
        misc/
            miscellaneous system-wide ASCII text files
            fonts/
                ???
            termcap
                terminal characteristics database; see termcap(5)
        mk/ templates for make; see make(1)
        nls/
            national language support files
        security/
            data files for security policies such as mac_lomac(4)
        sendmail/
            sendmail(8) configuration files
        skel/
            example ~. (dot) files for new accounts
        snmp/
            MIBs, example files and tree definitions for the SNMP daemon
            defs/
                tree definition files for use with gensnmptree(1)
            mibs/
                MIB files
        syscons/
            files used by syscons; see syscons(4)
            fonts/
                console fonts; see vidcontrol(1) and vidfont(1)
            keymaps/
                console keyboard maps; see kbdcontrol(1) and kbdmap(1)
            scrnmaps/
                console screen maps
        sysroot/
            files necessary for the -sysroot compiler/linker argument to build non-native binaries.
            VERSION/
                files for FreeBSD release VERSION. By convention, “VERSION” matches uname(1) -r.
                MACHINE.MACHINE_ARCH/
                    represent the binary ABI for these files. “MACHINE” matches uname(1) -m. “MACHINE_ARCH” matches uname(1) -p.
        tabset/
            tab description files for a variety of terminals; used in the termcap file; see termcap(5)
        vi/ localization support and utilities for vi(1)
        vt/ files used by vt; see vt(4)
            fonts/
                console fonts; see vidcontrol(1) and vidfont(1)
            keymaps/
                console keyboard maps; see kbdcontrol(1) and kbdmap(1)
        zoneinfo/
            timezone configuration information; see tzfile(5)

    src/
        FreeBSD source code; see development(7)

        bin/
            source code for files in /bin
        cddl/
            utilities covered by the Common Development and Distribution License
        contrib/
            source code for contributed software
        crypto/
            source code for contributed cryptography software
        etc/
            source code for files in /etc
        gnu/
            utilities covered by the GNU General Public License
        include/
            source code for files in /usr/include
        kerberos5/
            build infrastructure for Kerberos version 5
        lib/
            source code for files in /lib and /usr/lib
        libexec/
            source code for files in /usr/libexec
        release/
            files required to produce a FreeBSD release
        rescue/
            source code for files in /rescue
        sbin/
            source code for files in /sbin
        secure/
            build directory for files in /usr/src/crypto
        share/
            source for files in /usr/share
        stand/
            boot loader source code
        sys/
            kernel source code
            amd64/
                AMD64 architecture support
            arm/
                ARM architecture support
            arm64/
                ARMv8 architecture support
            cam/
                cam(4) and ctl(4)
            cddl/
                CDDL-licensed optional sources, including ZFS and DTrace
            ddb/
                ddb(4)
            fs/ most filesystems
            dev/
                device drivers
            geom/
                geom(4)
            i386/
                i386 (32 bit) architecture support
            kern/
                main part of the kernel
            net80211/
                net80211(4)
            netgraph/
                netgraph(4)
            netinet/
                inet(4)
            netinet6/
                inet6(4)
            netipsec/
                ipsec(4)
            netpfil/
                ipfw(4) and pf(4)
            opencrypto/
                crypto(7)
            powerpc/
                PowerPC/POWER architecture support
            riscv/
                RISC-V architecture support
            security/
                audit(4) and mac(4)
            sys/
                kernel headers
            ufs/
                Unix File System
            x86/
                code shared by AMD64 and i386 architectures
        targets/
            support for experimental DIRDEPS_BUILD
        tests/
            source code for files in /usr/tests
        tools/
            tools used for maintenance and testing of FreeBSD
        usr.bin/
            source code for files in /usr/bin
        usr.sbin/
            source code for files in /usr/sbin

    tests/
        The FreeBSD test suite; see tests(7)

/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)

        jobs/
            directory containing job files
        spool/
            directory containing output spool files

    backups/
        miscellaneous backup files
    cache/
        miscellaneous cached files

        pkg/
            cached packages for pkg(8)

    crash/
        default directory to store kernel crash dumps; see crash(8) and savecore(8)
    cron/
        files used by cron; see cron(8)

        tabs/
            crontab files; see crontab(5)

    db/ miscellaneous automatically generated system-specific database files
    empty/
        empty directory for use by programs that need a specifically empty directory. Used for instance by sshd(8) for privilege separation
    games/
        miscellaneous game status and score files
    heimdal/
        Kerberos server databases; see kdc(8)
    log/
        miscellaneous system log files

        utx.lastlogin
            last login log; see getutxent(3)
        utx.log
            login/logout log; see getutxent(3)

    mail/
        user mailbox files
    msgs/
        system messages database; see msgs(1)
    preserve/
        temporary home of files preserved after an accidental death of an editor; see ex(1)
    quotas/
        file system quota information files
    run/
        system information files describing various info about system since it was booted

        bhyve/
            bhyve vm unix domain sockets
        ppp/
            writable by the “network” group for command connection sockets; see ppp(8)
        utx.active
            database of current users; see getutxent(3)

    rwho/
        rwho data files; see rwhod(8), rwho(1), and ruptime(1)
    spool/
        miscellaneous printer and mail system spooling directories

        clientmqueue/
            undelivered submission mail queue; see sendmail(8)
        ftp/
            commonly ~ftp; the anonymous ftp root directory
        mqueue/
            undelivered mail queue; see sendmail(8)
        output/
            line printer spooling directories

    tmp/
        temporary files that are kept between system reboots

        vi.recover/
            the directory where recovery files are stored

    yp/ the NIS maps; see yp(8)

NOTES
This manual page documents the default FreeBSD file system layout, but the actual hierarchy on a given system is defined at the system administrator's discretion. A well-maintained installation will include a customized version of this document.

SEE ALSO
apropos(1), find(1), grep(1), ls(1), whereis(1), which(1)

HISTORY
A hier manual page appeared in AT&T UNIX.