Files for Linux

Today's feeling: folder meaning under the Linux root directory

Bin knowledge, binary files, and their use depends on the system or application. That is, in general, the machine code, assembly language compiled results, (DOS under the assembly language compiled with. com file similar), with Debug, Winhex,u_edit and other software open (usually not necessarily can understand what is not only proficient in assembly language) all the files, No matter what the suffix name is, it is divided into two forms. 　　Text and binary. A binary abbreviation of a file format. A file with a suffix named. bin just wanted to indicate that it is binary format., but it does not indicate that it is necessarily associated with an application.
A directory under the/dev:linux operating system for storing hardware device information, with direct access to the hardware under its directory
What is initrd.img and what is it for?
Initrd.img is a very important file in the Linux boot process, and if you compile the kernel, compile a subset of the functionality into Loadable modules. If the drive of some devices of the system is compiled into a loadable module, then if INITRD=/PATH_TO_INITRD.IMG is not specified at startup, then the system starts or fails, or a device cannot be used (like a network card or other device) after booting.
Medium, Medium, Medium, intermediate, Media, media
The Proc,proc file system is a pseudo-file system that only exists in memory and does not occupy external memory space. It provides an interface for accessing system kernel data in a file system manner. Users and applications can get system information through proc, and can change certain parameters of the kernel. Because the information of the system, such as the process, is dynamically changed, so when the user or application reads the proc file, the proc file system dynamically reads the required information from the system kernel and submits it.
Selinux,selinux (security-enhanced Linux) is the implementation of the U.S. National Security Agency (NSA) for mandatory access control, which is linux® The most outstanding new security subsystem. The NSA, with the help of the Linux community, has developed an access control system that, under the constraints of the access control system, can access only those files that are needed in his tasks. SELinux is installed on Fedora and Red Hat Enterprise Linux By default and can also be used as an easy-to-install package on other distributions.
sys-System Copy command. The copy command can also copy files to the target disk, but the destination disk cannot be a startup disk. Because these 3 system files need to be located at a specific location on the startup disk. SYS to Io.sys,msdos the DOS system files on the current drive. SYS and Command.com are transferred to the specified drive for creating the boot disk.
/usr is located in the root directory, and USR itself is the abbreviation for Unix System Resource, which stores the utility in its directory.
boot, boot loader, the file is divided into boot loader (boot loading) and operating systems (operating system) two parts.
etc, System configuration file
LIB, library file format, simulation model Description library file, shared function library
MNT, loading other disk nodes
root, in Unix systems (such as AIX, BSD, etc.) and Unix-like systems (such as Debian, Redhat, Ubuntu, and other distributions of Linux) and Android, the system's Superuser is generally named Root. Root is the only superuser in the system, with all the privileges in the system, such as starting or stopping a process, deleting or adding users, adding or disabling hardware, and so on.
source, which returns or sets a string expression that indicates the name of the object or application that originally generated the error. Readable/writable. Indicates that the Source property is a string expression that specifies the object that generated the error, which is usually the class name of the object or the ID of the program design. Use source to provide a message when the program code cannot handle errors that are caused by the object being accessed. For a class module, Source should contain a name with the Project.class form. When an unexpected error occurs in the code, the Source property automatically fills in the data. For errors in the standard module, Source contains the project name. For errors in a class module, Source contains the name of the form that has the project.class.
Tftpboot, which transmits the compiled code to the embedded chip via TFTP, is the transfer tool between the host and the Development Board.
var, a Var:Pascal:VAR in computer language, is used in Pascal as a reserved word for a program to define variables. such as: Var A:integer; (define variable A, type is integer) var u:array1. 100of integer; (define array U, subscript from 1 to 100, array cell type is integer)
Cd-rom,cd-rom (Compact Disc read-only Memory) is a CD-ROM that is used on a computer. Such discs can only be written to data once, and the information will be permanently stored on the disc so that the information is read through the disk drive. The CD format was originally designed for the storage and playback of music, and in 1985 the Yellow Book standards developed by Sony and Philips made this format adaptable to a variety of binary data. Some CD-ROMs store music and computer data, which can be played by CD players, and computer data can only be processed by a computer.
Home, home, homes, home, HQ,
Lost+found, storing repaired or damaged files, usually there is nothing inside, if there is something inside, then you should pay attention to, open this folder need to use root
Opt,opt (Optimized Production Technology, the best production technology) is a technology to improve production management, the Israeli physicist Eli Goldratt in the 70 's, to arrange the production of manpower and material scheduling methods.
Sbin, an important system program,/bin is generally a common executable program, and/sbin more for the system Management programs and service programs
s should be the word system
SRV, which is a type of resource record that is supported in the DNS server's database, records which computer has provided the service with such a simple information SRV record: The app is typically set for Microsoft Active Directory. DNS can be independent of Active Directory, but Active Directory must have DNS Help to work. In order for the Active Directory to work properly, the DNS server must support service location (SRV) resource records, which map the service name to the server name that provides the service. Active Directory clients and domain controllers use SRV resource records to determine the IP address of the domain controller.
TMP, when you use the Windows operating system, you may often find some files with the suffix tmp in the C packing directory and a temp directory found in the Windows directory. Some people who have just come into contact with the computer may find it puzzling, this is something, I have not built such a file Ah!
In fact, this is a temporary file generated by Windows, temporary files are created when you download and mount the software, open e-mail and instant messaging programs in the file or transfer files, after some time, these obsolete temporary files (may be quite large) may take up a lot of hard disk space, Accumulate hard disk fragmentation and reduce system performance. For example, using Word to edit a document, also found in the word's installation directory, a batch of ~ beginning, tmp end of the file, this is the temporary file generated by word, if your word has not been closed, want to delete them, but may find how to delete, the system repeatedly prompts read and write protection, this is good? The following is a comprehensive discussion of these interim documents and the approach to their treatment.
The Vmlinuz is a bootable, compressed kernel. "VM" stands for "Virtual Memory". Linux supports virtual memory, unlike older operating systems such as DOS, which have 640KB memory limitations. Linux is able to use hard disk space as virtual memory, hence the name "VM". 　　Vmlinuz is an executable Linux kernel, which is located in/boot/vmlinuz, which is generally a soft link. 　　There are two ways to build a vmlinuz. The first is to compile the kernel through "make zimage" created, and then through: "Cp/usr/src/linux-2.4/arch/i386/linux/boot/zimage/boot/vmlinuz" generated. 　　Zimage is suitable for small cores, it exists for backwards compatibility. Second, the kernel compiles by command make Bzimage, and then through: "Cp/usr/src/linux-2.4/arch/i386/linux/boot/bzimage/boot/vmlinuz" generated. Bzimage is a compressed kernel image, it should be noted that bzimage is not compressed with bzip2, the BZ in Bzimage is prone to misunderstanding, BZ said "Big Zimage". 　　B in Bzimage is the meaning of "big". Zimage (Vmlinuz) and Bzimage (Vmlinuz) are compressed with gzip. Not only are they a compressed file, they are also embedded with the Gzip decompression code at the beginning of these two files. 　　So you can't unpack vmlinuz with Gunzip or GZIP–DC. The kernel file contains a miniature gzip to decompress the kernel and boot it. The difference is that the old Zimage unzip the kernel to low-end memory (the first 640K), bzimage the kernel to high-end memory (1M or more). If the kernel is small, you can use one of the zimage or Bzimage, and the two modes of booting the system run the same. 　　The large kernel uses bzimage and cannot use Zimage. 　　Vmlinux is an uncompressed kernel, Vmlinuz is a compressed file of Vmlinux. Vmlinux-2.4.20-8 is an uncompressed kernel, vmlinuz-2.4.20-8 is a compressed file of vmlinux-2.4.20-8.

Files for Linux