.DS_Store

This file contains Finder settings, such as icon location and windowsize. The file will appear in any directory thatyou've viewed with the Finder.

.Trashes/

This directory contains files that have been dragged to the Trash. Ona boot volume, such files are stored in~/.Trash. On a non-boot volume, these files are in/.Trashes/uid/.

.hidden

This file contains a list of files that should be invisible to theFinder.

.vol/

This directory maps HFS+ file IDs to files. If you know afile's ID, you can open it using/.vol/id.

Applications (Mac OS 9)/

This directory contains all your OS 9 applications, ifyou've got Mac OS X and Mac OS 9 installed.

Applications/

This directory holds all your Mac OS X applications. ItsUtilities subdirectory includes lots of usefulthings, such as Terminal and Console.

Desktop DB

This file, along with Desktop DF, contains thedesktop database that is rebuilt when you click Rebuild Desktop inSystem Preferences Classic.

Desktop DF

See Desktop DB.

Desktop Folder/

This directory is the Mac OS 9 desktop folder.

Developer/

This directory contains Apple's Developer Tools anddocumentation. This is only available if you have installed theDeveloper Tools.

Documents/

This is the Mac OS 9 documents folder.

Library/

This directory contains support files for locally installedapplications, among other things. See Table A-4, later in thischapter.

Network/

This directory contains network-mountedApplication, Library, andUsers directories, as well as aServers directory, which contains directoriesmounted by the automount daemon.

Shared Items/

In Mac OS 9, this folder gave multiuser systems a place where userscould store files that other users could access.

System Folder/

This is the Mac OS 9 System Folder.

System/

This directory contains a subdirectory, Library,which holds support files for the system and system applications,among other things. See Table A-3, later in this chapter.

Temporary Items/

This directory contains temporary files used by Mac OS 9.

TheVolumeSettingsFolder/

This directory keeps track of details such as open windows anddesktop printers.

Trash/

This directory is where Mac OS 9 stores deleted files until the Trashis emptied.

Users/

This directory contains home directories for the users on the system.The root user's home directoryis /var/root.

VM Storage

This is the Mac OS 9 virtual memory file.

Volumes/

This directory contains all mounted filesystems, including removablemedia and mounted disk images.

automount/

This directory handles static NFS mounts for theautomount daemon.

bin/

This directory contains essential system binaries.

cores/

This directory is a symbolic link (or symlink)to /private/cores. If core dumps are enabled(with tcsh'slimit andbash/sh'sulimit commands--see thetcsh and bash manpages formore details), they will be created in this directory ascore.pid.

dev/

This directory contains files that represent various devices. SeeTable A-6, later in this chapter.

etc/

This directory contains system configuration files. See Table A-2,later in this chapter. The directory is a symbolic link to/private/etc.

lost+found

This directory stores orphaned files discovered byfsck.

mach

This is a symbolic link to the /mach.sym file.

mach.sym

This file contains kernel symbols. It is generated during each bootby /etc/rc.

mach_kernel

This is the Darwin kernel. See Chapter 7 for more information about the kernel.

private/

This private directory contains the tmp,var, etc, andcores directories.

sbin/

This directory contains executables for system administration andconfiguration.

tmp/

This directory holds temporary files. It is a symbolic link to/private/tmp.

usr/

This directory contains BSD Unix applications and support files.

var/

This directory contains frequently modified files, such as log files.It is a symbolic link to /private/var.

6to4.conf

Configuration file for encapsulating IPv6 within IPv4. Seeip6config(8).

X11/

X11 configuration directory. This will be present only if you haveinstalled XDarwin.

acgid/

File that contains configuration files foracgid, a bridge between Apache and ACGI-capablescripting languages, such as AppleScript. Mac OS X Server only. Forequivalent functionality under Mac OS X, seehttp://www.sentman.com/acgi/.

afpovertcp.cfg

File that causes Mac OS X to use TCP/IP as the default transport forApple File Protocol (AFP). Use this file to configure the defaultsfor AFP over TCP/IP.

appletalk.cfg

AppleTalk configuration file for routing or multihoming. See theappletalk.cfg(5) manpage.

authorization

File that controls how applications, such as installers, cantemporarily obtain root privileges.

bashrc

Global configuration file for bash, theBourne-again shell.

crontab

root'scrontab. See Section 2.3.1.

csh.cshrc

Global csh configuration file, processed whenthe shell starts up. If you have a .cshrc or.tcshrc file in your home directory,tcsh will execute its contents as well.

csh.login

Global csh login file, processed when a loginshell starts up. If you have a .login file inyour home directory, tcsh will execute itscontents as well.

csh.logout

Global csh logout file, processed when a userlogs out of a login shell.

cups/

Directory that contains configuration files for Common Unix PrintingSystem (CUPS).

daily

cron job that is run once a day (seecrontab). This is a symlink to/etc/periodic/daily/500.daily.

defaults/

Directory that contains default configuration files for applicationsand utilities.

diskspacemonitor/

Configuration files for diskspacemonitor, whichmonitors the amount of free disk space. Mac OS X Server only.

dumpdates

Dump date records created by dump(5), which isrun by /etc/daily.

find.codes

Description not available at time of writing; see errata page athttp://www.oreilly.com/catalog/mosxgeeks.

ftpusers

List of users who are prohibited from using FTP.

gdb.conf

Global gdb configuration file.

gettytab

Terminal configuration database.

group

Group permissions file. See Chapter 3 for moreinformation.

hostconfig

System configuration file that controls many of the startup itemsdescribed in Section 2.1.4 in Chapter 2.

hosts

Host database; a mapping of IP addresses to hostnames. You can usethis as a supplement to other Directory Services, such as DNS. Mac OSX 10.1 and earlier consulted this file only in single-user mode, butMac OS X 10.2 (Jaguar) uses this file at other times. For moreinformation, see Chapter 3.

hosts.equiv

List of trusted remote hosts and host-user pairs. This is used byrsh and is inherently insecure. You should usessh instead, which is a secure alternative. Seessh-keygen(1) to generate key pairs that can beused to set up a trust relationship with remote users.

hosts.lpd

List of hosts that are allowed to connect to the Unixlpd service.

httpd/

Directory that contains Apache's configuration files.

iftab

Configuration file for network interfaces.

inetd.conf

Internet super-server (inetd) configurationfile.

IPAliases

Configuration file for IP aliases.

kcpassword

Description not available at time of writing; see errata page athttp://www.oreilly.com/catalog/mosxgeeks.

kern_loader.conf

Description not available at time of writing; see errata page athttp://www.oreilly.com/catalog/mosxgeeks.

localtime

Symbolic link to your system's time zone, such as:/usr/share/zoneinfo/US/Eastern.

magic

Database of magic numbers used by the filecommand to determine a file's type.

mail/

Directory that contains configuration files forsendmail. Note that Open Directory handles themail aliases (see Chapter 3).

mail.rc

Global configuration file for /usr/bin/mail.

manpath.config

Configuration file for man.

master.passwd

Shadow passwd file. This is consulted only insingle-user mode. During normal system operation, Open Directorymanages user information (see Chapter 3).

moduli

System-wide prime numbers used for cryptographic applications such asssh.

monthly

Monthly cron job (seecrontab). This is a symlink to/etc/periodic/monthly/500.monthly.

motd

Message of the day. This is displayed each time you launch a newTerminal or log in remotely.

named.conf

Configuration file for named, the DNS daemon.For more details, see named(8).

networks

Network name database.

ntp.conf

Configuration file for the Network Time Protocol daemon, whichsynchronizes system time by accessing a remote server.

openldap/

Directory that contains configuration files for OpenLDAP, animplementation of the Lightweight Directory Access Protocol.

pam.d/

Directory that contains configuration files for PAM .

passwd

Password file. For more information, see Chapter 3.

periodic/

Directory that contains configuration files for theperiodic utility, which runscron jobs on a regular basis.

ppp/

Contains configuration files for Point-To-Point Tunneling Protocol(PPTP). Mac OS X Server only.

printcap

Printer configuration file for lpd. CUPSautomatically generates this file. For more information, seecupsd(8).

profile

Global profile for the Bourne-again shell.

protocols

Network protocol database.

racoon/

Directory that contains configuration files forraccoon, the IKE key management daemon.

rc

Startup script for multiuser mode.

rc.boot

Startup script for single-user mode.

rc.cleanup

Cleanup script invoked by /etc/rc.

rc.common

Common settings for startup scripts.

rc.netboot

Startup script for booting from the network using NetBoot.

resolv.conf

DNS resolver configuration.

resolver/

Contains files used to resolve hostnames.

rmtab

Remote NFS mount table.

rpc

RPC number-to-name mappings. Mac OS X 10.1 and earlier consulted thisfile only in single-user mode, but Mac OS X 10.2 (Jaguar) uses thisfile at other times. For more information, see Chapter 3.

rtadvd.conf

Configuration file for the router advertisement daemon. For moredetails, see rtadvd(8).

servermgrd/

Configuration files for the Server Manager daemon. Mac OS X Serveronly.

services

Internet service name database. Mac OS X 10.1 and earlier consultedthis file only in single-user mode, but Mac OS X 10.2 (Jaguar) usesthis file at other times. For more information, see Chapter 3.

shells

List of shells.

slpsa.conf

Configuration file for the service locator daemon(slpd).

smb.conf

Samba configuration file.

smb.conf.template

Template configuration file for Samba.

squirrelmail/

Configuration files for SquirrelMail, a web-based email client. Seehttp://www.squirrelmail.org. MacOS X Server only.

ssh_config

Global configuration file for OpenSSH client programs.

ssh_host_dsa_key

Private DSA host key for OpenSSH. This file, and the otherssh_host_* files, are created the first time youstart Remote Login in the Sharing System Preferences.

ssh_host_dsa_key.pub

Public DSA host key for OpenSSH.

ssh_host_key

Private host key for OpenSSH when using SSH 1 compatibility.

ssh_host_key.pub

Public host key for OpenSSH when using SSH 1 compatibility.

ssh_host_rsa_key

Private RSA host key for OpenSSH.

ssh_host_rsa_key.pub

Public RSA host key for OpenSSH.

sshd_config

Configuration file for the OpenSSH sshd daemon.

sudoers

Configuration file for the sudo command. Makesure you use the visudo command only to editthis file.

syslog.conf

syslogd configuration file.

ttys

Terminal initialization file.

ttys.installer

Description not available at time of writing; see errata page athttp://www.oreilly.com/catalog/mosxgeeks.

watchdog.conf

Configuration file for Mac OS X Server's watchdogservice. Watchdog restarts certain daemons if they die (similar toSystem V inittab).

webperfcache

File that contains configuration files for Mac OS XServer's webperfcache service,which sits between port 80 and your web server and caches staticpages.

weekly

Weekly cron job (seecrontab). This is a symlink to/etc/periodic/weekly/500.weekly.

xinetd.conf

Configuration file for xinetd, the extendedInternet superserver daemon.

xinetd.d/

File that contains service-specific configuration files forxinetd.

xtab

Description not available at time of writing; see errata page athttp://www.oreilly.com/catalog/mosxgeeks.

Axis/

Contains support files for Apache Axis. Mac OS X Server only.

Assistants/

Contains support files for the setup assistant. Mac OS X Server only.

Caches/

Contains caches used by various parts of the operating system.

CFMSupport/

Holds shared libraries used by Carbon applications.

Classic/

Description not available at time of writing; see errata page athttp://www.oreilly.com/catalog/mosxgeeks.

ColorPickers/

Includes localized resources for Mac OS X color pickers.

Colors/

Lists the names and values of colors used in the color picker control.

ColorSync/

Contains ColorSync profiles.

Components/

Contains application building blocks (components), such asAppleScript and color pickers. Components are not applicationsthemselves and are generally shared between applications.

CoreServices/

Contains system applications, such asSystemStarter, BootX, theFinder, and the login window.

Displays/

Contains ColorSync information for external monitors.

DTDs/

Contains document type definitions for XML documents used by thesystem, such as property lists.

Extensions/

Holds Darwin kernel extensions.

Extensions.kextcache

Contains information about extensions in the cache; a compressed XMLdocument.

Extensions.mkext

Contains the kernel extension cache. It is created at boot by/etc/rc.

Filesystems/

Contains drivers and utilities for various filesystems (MS-DOS,AppleShare, UFS, etc.).

Find/

Includes support files for Sherlock's contentindexing.

Fonts/

Contains core Mac OS X fonts.

Frameworks/

Holds a collection of reusable application frameworks, includingshared libraries, headers, and documentation.

Image Capture/

Contains device support files for the Image Capture application.

Java/

Contains Java class and jarfiles.

Keyboard Layouts/

Contains bundles that support internationalized keyboard layouts.

Keyboards/

Contains keyboard mappings.

Keychains/

Contains system-wide keychain files.(~/Library/Keychains contains per-userkeychains.)

LoginPlugins/

Contains helper applications that are launched as you log in.

Modem Scripts/

Contains modem configuration scripts.

MonitorPanels/

Includes panels used by System Preferences Displays.

OpenSSL/

Holds OpenSSL configuration and support files.

Perl/

Holds Perl Libraries.

PHP/

Contains PHP Libraries.

PreferencePanes/

Contains all the preference panes for the Preferences application.

Printers/

Contains printer support files.

PrivateFrameworks/

Holds private frameworks meant to support Mac OS X. These frameworksare not meant for programmers' use.

QuickTime/

Holds QuickTime support files.

QuickTimeJava/

Includes support files for the QuickTime/Java bridge.

Rulebooks/

Contains information used for text handling, such as word-breakingrules for hyphenation.

Screen Savers/

Contains screensavers that you can select from System Preferences Screen Saver.

ScriptingAdditions/

Includes AppleScript plug-ins and libraries.

Server Settings/

Contains plug-ins for the Server Settings utility. Mac OS X Serveronly.

ServerSetup/

Contains support files used when setting the initial serverconfiguration. Mac OS X Server only.

Services/

Contains services that are made available through the Services menu.

Sounds/

Contains sounds that are available in System Preferences Sound.

Speech/

Includes speech recognition and generation support files.

StartupItems/

Contains startup scripts as described in Chapter 2.

SystemConfiguration/

Contains plug-ins used to monitor various system activities (forApple use only).

SystemResources/

Contains precompiled header lists for the C compiler (see Section 5.1.1).

Tcl/

Holds Tcl libraries.

TextEncodings/

Contains localized text encodings.

User Template/

Lists localized skeleton files for user directories. See Section 3.8.3.

Application Support/

Contains support files for locally installed applications.

Audio/

Contains audio plug-ins and sounds.

Authenticators/

Contains authentication code for locally installed applications.

Caches/

Contains cached data used by various parts of the operating system.

CFMSupport/

Holds shared libraries used by Carbon applications.

ColorSync/

Contains user-installed ColorSync profiles and scripts.

Desktop Pictures/

Contains desktop pictures used by System Preferences Desktop.

Documentation/

Provides documentation for locally installed applications.

FTPServer/

Contains configuration files and the root folderof anonymous FTP server. Mac OS X Server only.

Filesystems/

Contains authentication support for the Apple Share network client.

Fonts/

Contains locally installed fonts.

Image Capture/

Contains locally installed scripts and plug-ins for the Image Captureapplication.

Internet Plug-Ins/

Contains locally installed browser plug-ins.

Java/

Contains locally installed Java classes (you can drop jar files into/Library/Java/Extensions), as well as a suitabledirectory to use as your $JAVA_HOME(/Library/Java/Home).

Keyboard Layouts/

Contains keyboard mappings.

Logs/

Holds logs for services such as Apple File Services, the CrashReporter, and the Directory Service.

Macintosh Manager/

Contains support files for the Macintosh Manager application (Mac OSX Server only).

Modem Scripts/

Holds support files for various modem types.

Perl/

Lists locally installed Perl modules (MakeMaker'sINSTALLSITELIB).

PreferencePanes/

Contains system preference panes for locally installed utilities suchas TinkerTool.

Preferences/

Lists global preferences.

Printers/

Lists printer drivers and utilities.

QuickTime/

Contains locally installed QuickTime components.

QuickTimeStreaming/

Contains the QuickTime Streaming Server (Mac OS X Server only).

Receipts/

Leaves a receipt in the form of a .pkg directoryafter you install an application with the Mac OS X installer. The.pkg directory contains a bill of materials file(.bom), which you can read with thelsbom command.

Screen Savers/

Lists locally installed screensavers.

Scripts/

Contains a variety of AppleScripts installed with Mac OS X.

StartupItems/

Lists locally installed startup items. See Section 2.2.

Tomcat/

Holds the Apache Tomcat Java Servlet and JSP server (Mac OS X Serveronly).

User Pictures/

Contains user pictures that are used in the login panel.

WebServer/

Contains the Apache CGI and document rootdirectories.

at/

Contains information about jobs scheduled with theat command.

backups/

Contains backups of the NetInfo database.

cron/

Contains user crontab files.

db/

Includes a grab bag of configuration and data files, including thelocate database, the NetInfo database, andnetwork interface information.

empty/

Description not available at time of writing; see errata page athttp://www.oreilly.com/catalog/mosxgeeks.

log/

Contains a variety of log files, includingsyslog, mail, and web server logs.

mail/

Contains inboxes for local users' email.

msgs/

Holds system-wide messages that were delivered using msgs-s.

named/

Includes various files used for local DNS services.

netboot/

Contains various files used for NetBoot.

root/

Serves as the root user's homedirectory.

run/

Holds PID files for running processes. Also contains working filesused by programs such as sudo.

rwho/

Contains information used by the rwho command.

servermgrd/

Contains runtime files used by the Server Manager daemon. Mac OS XServer only.

spool/

Serves as a spool directory for mail, printer queues, and otherqueued resources.

tmp/

Serves as a temporary file directory.

vm/

Contains your swap files.

yp/

Contains files used by NIS.

bpf[0-3]

Berkeley Packet Filter devices. See bpf(4).

console

The system console. This is owned by whoever is currently logged in.If you write to it, the output will end up in/var/tmp/console.log, which you can view withthe Console application(/Applications/Utilities).

cu.modem

Modem device for compatibility with the Unix cu(call up) utility.

disk[0-n]

Disk.

disk[0-n]s[0-n]

Disk partition. For example, /dev/disk0s1 is thefirst partition of /dev/disk0.

fd/

Devices that correspond to file descriptors. See thefd manpage for more details.

klog

Device used by syslogd to read kernel messages.

kmem

Image of kernel memory.

mem

Image of the system memory.

null

Bit bucket. You can redirect anything here, and it will disappear.

ptyp[0-f]

Master ends of the first sixteen pseudo-ttys.

pty[q-w][0-f]

Master ends of the remaining pseudo-ttys.

random

Source of pseudorandom data. See random(4).

rdisk[0-n]

Raw disk device.

rdisk[0-n]s[0-n]

Raw disk partition.

stderr

Symbolic link to /dev/fd/2.

stdin

Symbolic link to /dev/fd/0.

stdout

Symbolic link to /dev/fd/1.

tty

Standard output stream of the current Terminal or remote login.

tty.modem

Modem device.

ttyp[0-f]

Slave ends of the first sixteen pseudo-ttys.

tty[q-w][0-f]

Slave ends of the remaining pseudo-ttys.

urandom

Source of pseudorandom data, not guaranteed to be strong. Seerandom(4).

vn[0-3]

Pseudo disk devices.

zero

Infinite supply of null characters. Often used withdd to create a file made up of nullcharacters.