HIER(7)

NAME
hier - layout of filesystems

DESCRIPTION
An outline of the filesystem 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 filesystems

/altroot/
    alternate root filesystem, 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 CD devices for ISO-9660 file systems

/dev/
    block, character and other special device files

    MAKEDEV
        script for creating device files; see makedev(8)
    console
        the computer's console device
    drum
        system swap space; 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 process' controlling terminal device; 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
        filesystem export information; see mountd(8)
    fstab
        filesystem information; 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 ID's
    hosts.lpd
        trusted machines with printing privileges
    inetd.conf
        Internet server configuration file; see inetd(8)
    kerberosV/
        configuration files for the kerberos version V; see kerberos(8)
    localtime
        local timezone information; see ctime(3)
    mail/
        configuration files for sendmail(1)

        aliases*
            name 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, read by 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 configuration files; see mtree(8)
    named.*
    namedb/
        named configuration files and databases; see named(8)
    netgroup
        network groups; see netgroup(5)
    netstart
        network startup script
    networks
        network name data base; see networks(5)
    passwd
        World readable password file generated from master.passwd; see passwd(5), pwd_mkdb(8)
    phones
        remote host phone number data base; see phones(5)
    printcap
        system printer configuration; see printcap(5)
    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)
    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)
    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/
    mount point for the automounter; see amd(8)

/kern/
    mount point for the kern file system; see mount_kernfs(8)

/lib/
    dynamic linked libraries used by dynamic linked programs (such as those in /bin/ and /sbin/) that cannot rely upon /usr/lib/ being available.

/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

/netbsd
    pure kernel executable (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
    .login
        super-user start-up file
    .profile
        super-user start-up file
    .rhosts
        super-user id mapping between machines

/sbin/
    system programs and administration utilities used in both single-user and multi-user environments

/stand/
    programs used in a standalone environment

/tmp/
    temporary files, usually a mfs(8) memory-based filesystem (the contents of /tmp are usually not preserved across a system reboot)

/usr/
    contains the majority of the system utilities and files

    X11R6/
        X11 files
    X11R7/
        X11 files

        bin/
            X11 binaries
        include/
            X11 include files
        lib/
            X11 libraries

    bin/
        common utilities, programming tools, and applications
    games/
        the important stuff
    include/
        standard C 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 C++ compiler
        machine/
            machine specific include files
        net/
        netatalk/
            C include files for AppleTalk protocols miscellaneous network include files; see atalk(4)
        netinet/
            include files for Internet standard protocols; see inet(4)
        netinet6/
            include files for Internet protocol version 6; see inet6(4)
        netkey/
            include files for secret key management, used for security protocols; see ipsec(4)
        netnatm/
            C include files for native mode ATM
        nfs/
            C include files for NFS (Network File System)
        protocols/
            C include files for Berkeley service protocols
        sys/
            system C include files (kernel data structures)
        ufs/
            C include files for UFS (The U-word File System)

    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; normally a symbolic link or mounted filesystem
    pkg/
        packages maintained by groups other than the NetBSD Project.

        bin/
            contributed binaries
        include/
            contributed include files
        lib/
            contributed libraries
        libdata/
            contributed data files
        libexec/
            contributed daemons
        sbin/
            contributed system utilities

    pkgsrc/
        build descriptions ("packages") for the NetBSD packages system.

        distfiles/
            Where unchanged source archives are fetched to/stored
        packages/
            Where compiled binary packages are stored

        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 text files

        calendar/
            a variety of calendar files; see calendar(1)
        dict/
            word lists; see look(1) and spell(1)

            words
                common words
            web2
                words of Webster's 2nd International
            papers/
                reference databases; see refer(1)
            special/
                custom word lists; see spell(1)

        doc/
            miscellaneous documentation; source for most of the printed 4.3BSD manuals (available from the USENIX association)
        games/
            text 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/
            formatted manual pages
        me/ macros for use with the me(7) 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) macro package
        nls/
            message catalogs; see catgets(3)
        skel/
            sample initialization files for new user accounts
        tmac/
            text processing macros; see nroff(1) and troff(1)
        zoneinfo/
            timezone configuration information; see tzfile(5)
    tests/
        test programs; see atf-run(1) 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 distributions
    doc/
        documentation about the source tree (i.e., about the tree, not about how to use the built software.)
    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 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 Berkeley technical papers
            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

            acorn26/
                Acorn Archimedes, A-series and R-series systems
            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/
                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 support
            prep/
                PReP (PowerPC Reference Platform) and CHRP 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
            ibcs2/
                support for Intel Binary 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
            osf1/
                support for Digital UNIX ( formerly OSF/1) binaries
            ossaudio/
                support for OSS audio
            sunos/
                support for SunOS 4.x binaries; see compat_sunos(8)
            svr4/
                support for System V Release 4 binaries; see compat_svr4(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/ miscellaneous file systems
            adosfs/
                AmigaDOS file-system support; see mount_ados(8)
            cd9660/
                support for the ISO-9660 filesystem; see mount_cd9660(8)
            filecorefs/
                support for the Acorn RISC OS filecore filesystem; see mount_filecore(8)
            msdosfs/
                MS-DOS file system; see mount_msdos(8)
            ntfs/
                NTFS filesystem support; see mount_ntfs(8)
            ptyfs/
                pseudo-terminal device filesystem; see mount_ptyfs(8)
            smbfs/
                SMB/CIFS filesystem 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).
        ipkdb/
            support for kernel debugging over the network

        kern/
            support for the high kernel (system calls)
        lib/
            kernel libraries

            libkern/
                C library routines used in the kernel
            libsa/
                machine independent stand alone kernel library
            libz/
                compression library

        miscfs/
            miscellaneous file systems

            deadfs/
                kernel only dead file system
            fdesc/
                file descriptor file system; see mount_fdesc(8)
            fifofs/
                POSIX FIFO support
            genfs/
                kernel only generic file system
            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/
                kernel only special file system
            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
        netkey/
            Key database for IPsec networking support
        netnatm/
            ATM networking support
        nfs/
            NFS support
        stand/
            kernel standalone support
        sys/
            kernel (and system) include files
        ufs/
            local filesystem support

            ffs/
                the Berkeley Fast File System
            lfs/
                the 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 crash dumps; see savecore(8)
    cron/
        scheduled commands configuration files; see cron(8)
    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 and log 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 log; see utmp(5)
        lpd-errs.*
            printer daemon error logs; see lpd(8)
        maillog.*
            sendmail(1) 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/logout log; see utmp(5)

    mail/
        user system mailboxes
    msgs/
        system messages; see msgs(1)
    preserve/
        temporary home of files preserved after an accidental death of ex(1) or vi(1)
    quotas/
        filesystem quota information
    run/
        system information files, rebuilt after each reboot

        utmp
            database of current users; see utmp(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 vi(1)

    yp/ Databases and configuration for the NIS (YP) system; see nis(8).

SEE ALSO
apropos(1), ls(1), whatis(1), whereis(1), which(1), paths(3)

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