The following table describes the default directories in the /usr file system.
Table 43-2 Default Directories in the /usr File System
Directory | Description |
|---|---|
4lib | SunOS 4.1 binary compatibility package libraries |
5bin | Symbolic link to the /usr/bin directory |
X | Symbolic link to the /usr/openwin directory |
adm | Symbolic link to the /var/adm directory |
apache | Apache executables, loadable modules, and documentation |
aset | Directory for Automated Security Enhancement Tools (ASET) programs and files |
bin | Location for standard system commands |
ccs | C compilation programs and libraries |
demo | Demo programs and data |
dict | Symbolic link to the /usr/share/lib/dict directory, which contains the dictionary file used by the UNIX spell program |
dt | Directory or mount point for CDE software |
games | An empty directory, which is a remnant of the SunOS 4.0/4.1 software |
include | Header files (for C programs, etc.) |
iplanet | Directory server executables, loadable modules, and documentation |
j2se | Java 2 SDK executables, loadable modules, and documentation |
java* | Directories that contain Java programs and libraries |
kernel | Additional kernel modules |
kvm | Obsolete |
lib | Various program libraries, architecture-dependent databases, and binaries not invoked directly by the user |
local | Commands local to a site |
Symbolic link to the /var/mail directory | |
man | Symbolic link to the /usr/share/man directory |
net | Directory for network listener services |
news | Symbolic link to the /var/news directory |
oasys | Files for the Form and Menu Language Interpreter (FMLI) execution environment |
old | Programs that are being phased out |
openwin | Directory or mount point for OpenWindows software |
perl5 | Perl 5 programs and documentation |
platform | Supported platform files. For more information, see Table 43-3. |
preserve | Symbolic link to the /var/preserve directory |
proc | Directory for the proc tools |
pub | Files for online man page and character processing |
sadm | Various files and directories related to system administration |
sbin | Executables for system administration |
sbin/install.d | Custom JumpStart scripts and executables |
sbin/static | Statically linked version of selected programs from /usr/bin and /usr/sbin |
sbin/sparc7 and sparc9 | 32-bit and 64-bit versions of commands |
sfw | GNU and open source executables, libraries, and documentation |
share | Architecture-independent sharable files |
share/admserv5.1 | iPlanet Console and Administration Server 5.0 documentation |
share/audio | Sample audio files |
share/ds5 | iPlanet Directory Server 5.1 Documentation |
share/lib | Architecture-independent databases |
share/man | Solaris manual pages |
share/src | Source code for kernel, libraries, and utilities |
snadm | Programs and libraries related to system and network administration |
spool | Symbolic link to the /var/spool directory |
src | Symbolic link to the share/src directory |
tmp | Symbolic link to the var/tmp directory |
ucb | Berkeley compatibility package binaries |
ucbinclude | Berkeley compatibility package header files |
ucblib | Berkeley compatibility package libraries |
vmsys | Directory for Framed Access Command Environment (FACE) programs |
xpg4 | Directory for POSIX-compliant utilities |
The Platform-Dependent Directories
The following table describes the platform-dependent objects in the /platform and /usr/platform directories.
Table 43-3 The /platform and /usr/platform Directories
Directory | Description |
|---|---|
/platform | Contains a series of directories, one per supported platform that needs to reside in the root (/) file system. |
/platform/*/kernel | Contains platform-dependent kernel components, including the file unix, the core kernel that is platform- dependent. For more information, see kernel(1M). |
/usr/platform | Contains platform-dependent objects that do not need to reside in the root (/) file system. |
/usr/platform/*/lib | Contains platform-dependent objects similar to those objects found in the /usr/lib directory. |
/usr/platform/*/sbin | Contains platform-dependent objects similar to those objects found in the /usr/sbin directory. |
The Structure of Cylinder Groups for UFS File Systems
When you create a UFS file system, the disk slice is divided into cylinder groups, which is made up of one or more consecutive disk cylinders. The cylinder groups are then further divided into addressable blocks to control and organize the structure of the files within the cylinder group. Each type of block has a specific function in the file system. A UFS file system has these four types of blocks:
Block Type | Type of Information Stored |
|---|---|
Boot block | Information used when booting the system |
Superblock | Detailed information about the file system |
Inode | All information about a file |
Storage or data block | Data for each file |
The following sections provide additional information about the organization and function of these blocks.
The Boot Block
The boot block stores objects that are used in booting the system. If a file system is not to be used for booting, the boot block is left blank. The boot block appears only in the first cylinder group (cylinder group 0) and is the first 8 Kbytes in a slice.
The Superblock
The superblock stores much of the information about the file system, which includes the following:
Size and status of the file system
Label (file system name and volume name)
Size of the file system logical block
Date and time of the last update
Cylinder group size
Number of data blocks in a cylinder group
Summary data block
File system state
Path name of the last mount point
The superblock is located at the beginning of the disk slice, and is replicated in each cylinder group. Because the superblock contains critical data, multiple superblocks are made when the file system is created. Each superblock replica is offset by a different amount from the beginning of its cylinder group. For multiple-platter disk drives, the offsets are calculated so that a superblock appears on each platter of the drive. That way, if the first platter is lost, an alternate superblock can always be retrieved. Except for the leading blocks in the first cylinder group, the leading blocks that are created by the offsets are used for data storage.
A summary information block is kept within the superblock. The summary information block is not replicated, but is grouped with the primary superblock, usually in cylinder group 0. The summary block records changes that take place as the file system is used, and lists the number of inodes, directories, fragments, and storage blocks within the file system.