Root file systems should generally be relatively small, because including strict files and a small unusible file system is not easily damaged. Damaged root file systems generally means that this insurance should not be taken unless otherwise cannot be guided by a specific method (eg, from the floppy disk) system.
The root directory generally does not contain any files, in addition to possible standard system boot images, usually called / Vmlinuz. All other files are in the subdirectory of the root file system.
/ bin boots commands that the required commands or ordinary users may be used (possibly after boot startup).
/ sbin is similar / bin, but does not use ordinary users, although it can be used if necessary and allowed.
/ ETC specific machine configuration file.
/ Root root user's home directory.
The shared library required for the program on the lib root file system.
/ lib / modules core loadable module, especially those required to boot when the damage is reduced (such as network, and file system driver).
/ DEV device file.
/ TMP temporary file. The program that is boot started should use / var / tmp, not / TMP, because the former may be on a disk with more space.
/ boot Booter Loader (Bootstrap Loader), such as LILO. The core image is often here, not at the root directory. If there are many core pictures, this directory may become large, then you may use a separate file system better. Another reason is to ensure that the core image must be in the top 1024 cylinders of the IDE hard drive.
/ MNT system administrator temporary MOUNT installation point. The program does not automatically support installation to / mnt. / MNT can be divided into a subdirectory (such as / MNT / DOSA may be a floppy drive using the MSDOS file system, and / MNT / EXTA may be a floppy drive using an EXT2 file system).
/ Proc, / usr, / var, / home Other file system installation points.
The / etc directory contains many files. Some of them will be described below. Other you should know which program they belong to, and read the MAN page of the program. Many network configuration files are also in / etc, which are described in the Network Administration Guide.
/ etc / rc or /etc/rc.d or /etc/rc?.d start, or change the scripts or scripts of the Scripts or Scripts running when the run level is changed, and more detailed information sees about INIT.
/ etc / passwd user database, where the domain gives the username, real name, home directory, encrypted password, and other information. See the Passwd's MAN page.
/ etc / fdprm floppy disk parameter table. Note Different floppy disk formats. Set with SetFDPRM. More information See the SETFDPRM's MAN page.
/ etc / fstab starts Mount -a commands (in / etc / rc or equivalent boot file) Automatic Mount file system list. Under Linux, information is also included in the SWAP area enabled with swapon -a. See the 14.8.5 and Mount's MAN page.
/ etc / group is similar / etc / passwd, but instructions are not users but groups. See the GROUP's MAN page.
/ etc / inittab init configuration file.
/ etc / issu getty output information before the login prompt. It usually includes a short description or welcome information of the system. The content is determined by the system administrator.
/ etc / magic file configuration file. Instructions containing different file formats, FILE is based on it guess file type. See MAGIC and File MAN Pages.
/ etc / motd message of the day, automatically outputs after successful login. The content is determined by the system administrator. Frequently used for advertisement information, such as a warning of the shutdown time.
/ etc / mtab currently installed file system list. Initialized by Scripts and automatically update by the mount command. Requires a list of currently installed file systems, such as DF commands.
/ etc / shadow on the system on the system of shadow password software on the system. The shadow password file moves the encryption port in the / etc / passwd file to / etc / shadow, while the latter is only read to root. This makes the decipherous password more difficult. The /etc/login.defs login command configuration file.
/ etc / printcap is similar / etc / termcap, but for printers. The grammar is different.
/ etc / profile, /etc/csh.login, /etc/csh.cshrc login or started the file that Bourne or c shells executed. This allows the system administrator to establish a global default environment for all users. Each SHELL is seen in the MAN page.
/ etc / securetty confirms the security terminal, which terminal allows root to log in. Generally, only virtual console is usually listed, so it is impossible (at least very difficult) intrusion into the system through the MODEM or network, and get superuser privileges.
/ etc / shells lists trusted shells. The chsh command allows the user to change the login shell within the specified range of this document. Providing a machine FTP service service process FTPD checks if the user shell is listed in the / etc / shells file, if it is not allowed to log in.
/ etc / termcap terminal performance database. Explain what "escape sequence" control is used by different terminals. When writing programs, the escape sequence is not directly output (which can only work in a particular brand of terminals), but lookup the correct sequence of the work you want to do from / etc / termcap. In this way, most programs can run on most terminals. See the MAN page of Termcap, Curs_Termcap and Terminfo.
The / dev directory / dev directory includes device files for all devices. The device file is named with a specific agreement, which is described in the device list (see [ANV]). The device file is generated in the installation, and it can be described in / dev / makedev. /dev/makedev.local is a descriptor written by the system administrator as a local device file (or connection) (ie, such as some non-standard device drivers are not part of the standard MakeDev).
/ USR file system is often very large because all programs are installed here. All files in usr generally come from Linux Distribution; locally installed programs and other things under / usr / local. This may not need to reinstall all programs when upgrading a new system or new Distribution. / USR's somewhat subdirectory is listed below (some less important directories are omitted, more information see fsstnd).
/ usr / x11r6 x window system all files. To simplify the development and installation of X, the X files are not integrated into the system. X yourself like / usr under / usr / x11r6.
/ USR / X386 similar / usr / x11r6, but gives X11 Release 5.
/ usr / bin almost all user commands. Some commands are in / bin or / usr / local / bin.
/ USR / SBIN root file system unnecessary system management commands, such as most service programs.
/ USR / MAN, / USR / INFO, / USR / DOC man page, GNU information documentation, and various other document files.
/ usr / include C programming language header file. In order to consistency this, this is actually under / usr / lib, but it is traditionally supported this name.
/ USR / LIB program or subsystem constant data file, including some Site-Wide configuration files. Name lib comes from library; programmed raw stock in / usr / lib.
/ USR / LOCAL installs software and other files are placed here.
/ var / catman When the cache of the Man page is required to format it. The source file of the Man page generally exists / usr / man / man *; some MAN pages may have pre-formatted versions, exist / usr / man / cat *. Other MAN pages need to format, the formatted version of the version exists / var / man, so others do not wait to format the same page. (/ VAR / CATMAN is often cleared, just like clearing the temporary directory.) / VAR / lib system runs normally to change the file.
The variable data of the program installed in / var / local / usr / local (ie, the system administrator installed). Note that if necessary, even if the program is installed, other / var directories, such as / var / lock.
/ VAR / LOCK lock file. Many programs follow the conventions of a locked file in / var / lock to support them being using a particular device or file. Other programs notice this lock file, will not try to use this device or file.
/ VAR / log file log file, especially login (/ var / log / wtmp log all to system login and logging) and Syslog (/ var / log / messages store all core and system program information. / var / Log's documents are often uncertain, and should be cleared regularly.
/ var / run saves to a valid information file that is valid for the next boot. For example, / var / run / utmp contains information about the user currently logged in.
/ var / spool mail, news, print queues, and other queue works. Each different spool has its own subdirectory under / var / spool, for example, the user's mailbox is in / var / spool / mail.
/ VAR / TMP ratio / TMP is allowed to have a long-term temporary file. (Although the system administrator may not allow / var / tmp with very old files.)
/ Proc file system is a fake file system. It does not exist on a disk on disk. Instead, it is generated by the core in memory. Used to provide information about the system (Originally About Processes, Hence the Name). Hereinafter, some of the most important files and directories are explained. The / Proc file system has a more detailed description in the Proc Man page.
/ Proc / 1 About the information directory of the process 1. Each process has a directory named its process number under / proc.
/ Proc / CPUInfo processor information such as type, manufacturer, model, and performance.
/ Proc / Devices The list of device drivers currently running the core configuration.
/ Proc / DMA displays the current DMA channel.
/ Proc / FileSystems core configuration file system.
/ proc / interrupts Display Used Interrupt, And How Many of Each There Have Been.
/ Proc / Ioports currently used I / O ports.
/ proc / kcore system physical memory image. Like the physical memory size, but not actually occupying so many memory; IT IS generated on the fly as programs access it. (Remember: Unless you copy it where you copy it, there is no disk space under / proc. )
/ proc / kmsg core output message. Also sent to syslog.
/ proc / ksyms core symbol table.
/ Proc / loadAVG system "average load"; 3 unspeir indicators point out the current workload of the system.
/ Proc / MemInfo memory usage information, including physical memory and SWAP.
/ Proc / Modules currently loads which core modules.
/ Proc / Net Network Protocol Status Information.
/ proc / self to the symbolic connection of the process directory of the program that views / proc. It is a different connection when 2 processes view / proc. This is primarily facilitated to get its own process catalog.
The different state of the / PROC / STAT system, Such As the Number of Page Faults Since The System Was Booted./Proc/UPTIME system is started.
/ Proc / Version core version.
