HIER(7)

NAME
hier - layout of filesystems

DESCRIPTION
A sketch of the filesystem hierarchy.

/   Root directory.

/altroot/
    Alternate (backup) location for the root (‘/’) filesystem (see daily(8)).

/bin/
    User utilities fundamental to both single and multi-user environments. These programs are statically compiled and therefore do not depend on any system libraries to run.

/bsd
    Pure kernel executable (the operating system loaded into memory at boot-time).

/bsd.mp
    Pure kernel executable for multiprocessor machines.

/bsd.rd
    Installation kernel. The built-in RAM disk contains utilities which can be run without an external file system, so this kernel is useful for limited system maintenance too.

/bsd.sp
    Pure kernel executable for single processor machines.

/dev/
    Block and character device files.

    MAKEDEV
        Script for creating device files (see MAKEDEV(8)).
    fd/ File descriptor files (see fd(4)).

/etc/
    System configuration files and scripts.

    localtime
        Local time zone information (see ctime(3)).
    X11/
        Configuration files for the X11 window system.
    acme/
        Private keys for acme-client(1).
    amd/
        Contains map files for amd(8).
    authpf/
        Configuration files for the authenticating gateway user shell (see authpf(8)).
    examples/
        Example configuration files for base system daemons.
    firmware/
        Firmware files for various devices.
    fonts/
        Configuration files for X11 window system fonts.
    hotplug/
        Scripts for the hotplug daemon, hotplugd(8).
    iked/
        Configuration files for iked(8).
    isakmpd/
        Configuration files for isakmpd(8).
    ldap/
        Certificates and schema definition files for ldapd(8).
    login.conf.d/
        Additional login attributes for login.conf(5).
    mail/
        System mail configuration files.
    mtree/
        mtree(8) configuration files.
    npppd/
        npppd(8) configuration files.
    ppp/
        pppd(8) configuration files.
    raddb/servers/
        List of radius servers and their associated shared secrets for login_radius(8).
    rc.d/
        packages(7) start/stop scripts and subroutines for rc(8).
    rpki/
        TAL and configuration files for rpki-client(8).
    signify/
        Key files used by signify(1).
    skel/
        Example ‘’. (dot) files for new accounts.
    skey/
        One-time password user database for skey(1).
    ssh/
        Configuration files for ssh(1) and sshd(8).
    ssl/
        OpenSSL configuration files (see openssl(1)).

/home/
    Default location for user home directories.

    _sysupgrade/
        Download location for sysupgrade(8).

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

/root/
    Default home directory for the superuser.

/sbin/
    System programs and administration utilities fundamental to both single and multi-user environments. Most of these programs are statically compiled and therefore do not depend on any system libraries to run.

/tmp/
    Temporary files that are not preserved between system reboots. Periodically cleaned by daily(8).

/usr/
    Contains the majority of user utilities and applications.

    X11R6/
        Files required for the X11 window system.

        bin/
            X11 binaries.
        include/
            X11-specific C include files.
        lib/
            X11 archive libraries.

            X11/
                Default configuration files for X11 and companion applications.
            modules/
                Various libraries and drivers for the X11 window system.
            pkgconfig/
                Package metadata for pkg-config(1).
            xorg/
                Data files used by the X server.

        man/
            X11 manual pages.
        share/
            Architecture independent data files.

    bin/
        Common utilities, programming tools, and applications.
    games/
        Useful and semi-frivolous programs.
    include/
        Standard C include files.

        arpa/
            C include files for Internet service protocols.
        c++/
            Include files for the Clang C++ compiler.
        cbor/
            C include files for the Concise Binary Object Representation (CBOR) library.
        crypto/
            C include files for the cryptographic libraries.
        ddb/
            C include files for the kernel debugger (see ddb(4)).
        dev/
            Device-specific C include files.
        fido/
            C include files for the U2F/FIDO2 communication library.
        g++/
            Include files for the GNU C++ compiler.
        isofs/
            C include files for the ISO standard file systems (currently only cd9660).
        llvm/
            C++ include files for LLVM.
        llvm-c/
            C include files for LLVM.
        machine/
            Machine specific C include files.
        miscfs/
            C include files for miscellaneous file systems.
        msdosfs/
            C include files for MS-DOS file system.
        net/
            Miscellaneous network C include files.
        net80211/
            C include files for 802.11 wireless networking.
        netinet/
            C include files for Internet standard protocols (see inet(4)).
        netinet6/
            C include files for Internet protocol version 6 (see inet6(4)).
        netmpls/
            C include files for the MPLS protocol.
        nfs/
            C include files for NFS (Network File System).
        ntfs/
            C include files for NTFS file system.
        openssl/
            C include files for the OpenSSL library (see ssl(8)).
        protocols/
            C include files for Berkeley service protocols.
        readline/
            C include files for the readline(3) library.
        rpc/
            C include files for remote procedure calling (see rpc(5)).
        rpcsvc/
            C include files for rpcsvc.
        scsi/
            SCSI-specific C include files.
        sys/
            System C include files (kernel data structures).
        ufs/
            C include files for UFS (the U-word File System).
        uvm/
            C include files for the virtual memory interface.

    lib/
        System libraries. See intro(3) for a description of library types.
    libdata/
        Miscellaneous utility data files.

        cvs/
            Placeholder for user contributed cvs(1) code/scripts.
        ldscripts/
            ELF linker scripts.
        perl5/
            Data files for perl(1).

    libexec/
        System daemons and utilities (executed by other programs).

        auth/
            Login scripts used to authenticate users (for BSD Authentication).
        cvs/contrib/
            User contributed cvs(1) scripts.
        lpr/
            Contains the lpf filter for lpd(8).
        radiusd/
            Authentication modules for radiusd(8).
        snmpd/
            SNMP subagents.

    local/
        Local executables, libraries, etc.
    mdec/
        Boot-related executables.
    obj/
        Architecture specific target tree produced by building the /usr/src tree.
    ports/
        The OpenBSD ports collection (see ports(7)).
    sbin/
        System daemons and utilities (executed by users).
    share/
        Architecture independent data files.

        calendar/
            Variety of pre-fab calendar files (see calendar(1)).
        dict/
            Word lists (see look(1) and spell(1)).

            american
                Spellings preferred in American usage.
            british
                Spellings preferred in British usage.
            propernames
                List of proper names.
            stop
                Forms that would otherwise be derivable by spell(1) from words in the other files in /usr/share/dict, but should not be accepted.
            web2
                Words from Webster's 2nd International.
            web2a
                Additional words from Webster's.
            words
                Common words.
            papers/
                Reference databases.
            special/
                Custom word lists.

        doc/
            Miscellaneous documentation.
        games/
            ASCII text files used by various games.
        info/
            Texinfo source files.
        locale/
            Locales for multi-language support.
        man/
            Manual pages.

            man1/
                General commands (tools and utilities).
            man2/
                System calls and error numbers.
            man3/
                Libraries.
            man3p/
                perl(1) programmers' reference guide.
            man4/
                Special files and hardware support.
            man5/
                File formats.
            man6/
                Games.
            man7/
                Miscellaneous.
            man8/
                System maintenance and operation commands.
            man9/
                Kernel internals.

        misc/
            Miscellaneous system-wide ASCII text files.

            termcap
                Terminal characteristics database (see termcap(5)).
            pcvtfonts/
                Additional console fonts.

        mk/ Templates for make(1).
        relink/
            Link kit for boot-time kernel and library relinking.
        snmp/
            Data files for snmpd(8).

            mibs/
                Management Information Base (MIB) definitions.

        tabset/
            Tab description files for a variety of terminals; used in the termcap file (see termcap(5)).
        terminfo/
            Compiled terminal characteristic files (see terminfo(5)).
        texinfo/
            Templates for texinfo(5).
        zoneinfo/
            Time zone configuration information (see tzfile(5)).

    src/
        BSD and/or local source files.

        bin/
            Source for files in /bin.
        distrib/
            Source for making distribution sets.
        etc/
            Source for files in /etc.
        games/
            Source for files in /usr/games.
        gnu/
            Source for files under GPL or other restrictive licenses.
        include/
            Source for files in /usr/include.
        lib/
            Source for files in /usr/lib.
        libexec/
            Source for files in /usr/libexec.
        regress/
            Regress framework.
        sbin/
            Source for files in /sbin.
        share/
            Source for files in /usr/share.
        sys/
            Kernel source files.
        usr.bin/
            Source for files in /usr/bin.
        usr.sbin/
            Source for files in /usr/sbin.

    xenocara/
        Source for the X11 window system.

    xobj/
        Architecture specific target tree produced by building the /usr/xenocara tree.

/var/
    Multi-purpose log, temporary, transient, and spool files.

    account/
        System accounting files.

        acct
            Execution accounting file (see acct(5)).

    agentx/
        Master socket for AgentX-based backends, managed by snmpd(8).
    audit/
        Audit logs.
    authpf/
        PID file for authpf(8).
    backups/
        Miscellaneous backup files.
    cache/
        Data cached for programs.
    crash/
        Crash dumps written by savecore(8).
    cron/
        Spools and configuration files for cron(8) and at(1).

        atjobs/
            at(1) jobs.
        tabs/
            Individual crontab(1) files.

    db/ Miscellaneous, automatically generated system-specific database files.
    empty/
        Generic chroot(2) directory.
    games/
        Miscellaneous game status and log files.
    log/
        Miscellaneous system log files.

        wtmp
            Login/logout log (see wtmp(5)).
        rdist/
            Log files for rdist(1).

    mail/
        User mailbox files.
    nsd/
        Database and zone files for nsd(8).
    quotas/
        Filesystem quota information files.
    run/
        System information files describing various info about the system since it was booted.

        rc.d/
            Details of currently running daemons; used by rc.d(8).
        utmp
            Database of current users (see utmp(5)).

    spool/
        Miscellaneous printer and mail system spooling directories.

        ftp/
            Commonly ~ftp; the anonymous ftp root directory.
        lock/
            Lock files for utilities such as pppd(8).
        output/
            Line printer spooling directories.
        smtpd/
            Mail spool for smtpd(8).

    sysmerge/
        Checksum files and reference sets for sysmerge(8).
    syspatch/
        Rollback tarballs and patch files for syspatch(8).
    tmp -> ../tmp
        A symbolic link to the system /tmp directory. To protect other users of /var from overfill conditions, this is no longer a space you can trust to retain storage over a reboot. Periodically cleaned by daily(8).
    unbound/
        Configuration files for unbound(8).
    www/
        Configuration files for httpd(8).
    yp/ Files for the yp(8) subsystem.

SEE ALSO
apropos(1), find(1), locate(1), whatis(1), whereis(1), which(1)

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