Disk Management 2
Link Files
File linking can be created in UNIX file systems. The file is only available in one place on the file system, but can be accessed in many places only once. The link files are not functionally different from short-cuts in the MS-Windows environment. The goal is to provide users with unobtrusive access to files and directories.The link files in the MS-Windows operating system are ordinary files and are interpreted by the shell (explorer.exe). When a different shell is used, the destination file can not be reached via the link files. Conversely, in UNIX operating systems, link files are a feature provided directly by the file system. Even if the shell changes in UNIX, the mechanism of link files can continue to work.
There are two types of link files in UNIX. Hard link and symbolic link. The file type of the symbolic link files is the character "l". The access authorities are also "rwxrwxrwx". When accessing the file with a link, the access control authority of the target file is valid, so access authorities of the link files are insignificant.
A link to the link file can also be defined. When you access a link file, all links are routed by the file system and finally the actual file is reached.
Archive Commands
tar (Tape ArchiveR) - archives files and directories. Archiving creates a single large archive file that can be saved on the tape media by adding all the files you have made."-c" means create and allows creation of archive file
"-t" allows the archive to be tested.
"-x" will open the archive.
"-v" means verbose, and lists the files in the archive when it is being created, tested, and opened.
"-f file" specifies that the archive in the file name is to be used. If the "-f" option is not used, the standard input device is used for opening and testing, and the standard output device is used for creating.
Zip / unzip - Creates and opens zip files that we know quite well from the MS-Windows platform.
You can specify the Compression level between zip [-1 ..- 9]. "-1" is the worst compression (fast), "-9" is the best compression (slow).
Compression Commands
compress - a compression tool that has been around forever in all UNIX's. It compresses the file given as parameter and saves it as ".z" extension, also deletes the original file.The behavior of gzip is the same as compress, but provides a much higher compression ratio than compress when the file extensions are ".gz".
The behavior of bzip2 is the same as compress and gzip but provides a much higher compression ratio than gzip while the file extensions are ".bz2".
compress, gzip and bzip2 are not archive programs; They only compress.
GNU tar software also has the ability to compress gzip and bzip2 formats while it is being archived; The -z parameter can be used to compress gzip.
Apart from this software there are many more compression commands (7zip, lbzip2, xz, lrzip). You can choose to compress these software with different capabilities depending on the structure of the file.
To read my previous article: Disk Management 1
