|
Coreutils
The GNU Core Utilities or coreutils is a collection of GNU software that implements many standard, Unix-based shell commands. The utilities generally provide POSIX compliant interface when the environment variable is set, but otherwise offers a superset to the standard interface. For example, the utilities support long options and options after parameters. This environment variable enables a different functionality in BSD. Similar collections are available in the FOSS ecosystem, with a slightly different scope and focus (less functionality), or license. For example, BusyBox which is licensed under GPL-2.0-only, and Toybox which is licensed under 0BSD. Commands The commands implemented by coreutils are listed below. Throughout this article and customary for Unix-based systems, the term ''file'' refers to all file system items including regular files and special files such as directories. File utilities * chcon Changes file security context ( SELinux) * chgrp Chan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dd (Unix)
dd is shell command for reading, writing and converting file data. Originally developed for Unix, it has been implemented on many other environments including Unix-like operating systems, Windows, Plan 9 and Inferno. The command can be used for many purposes. For relatively simple copying operations, it tends to be slower than domain-specific alternatives, but it excels at overwriting or truncating a file at any point or seeking in a file. The command supports reading and writing files, and if a driver is available to support file-like access, the command can access devices too. Such access is typically supported on Unix-based systems that provide file-like access to devices (such as storage) and special device files (such as /dev/zero and /dev/random). Therefore, the command can be used for tasks such as backing up the boot sector of a drive, and obtaining random data. The command can also support converting data while copying; including byte order swapping and conve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chmod
is a shell command for changing access permissions and special mode flags of files (including special files such as directories). The name is short for ''change mode'' where ''mode'' refers to the permissions and flags collectively. The command originated in AT&T Unix version 1 and was exclusive to Unix and Unix-like operating systems until it was ported to other operating systems such as Windows (in UnxUtils) and IBM i. In Unix and Unix-like operating systems, a system call with the same name as the command, , provides access to the underlying access control data. The command exposes the capabilities of the system call to a shell user. As the need for enhanced file-system permissions grew, access-control lists were added to many file systems to augment the modes controlled via . The implementation of bundled in GNU coreutils was written by David MacKenzie and Jim Meyering. Use Although the syntax of the command varies somewhat by implementation, it generally acc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Df (Unix)
df, short for ''disk free'', is a shell command for reporting the amount of available storage space on file systems on which the user has read access. is typically implemented using the or system calls. The Single Unix Specification (SUS) specifies that space is reported in blocks of 512 bytes, and that at a minimum, it reports the file system names and the amount of free space. Using 512-bytes as the unit of measure is a historical practice and maintains compatibility with ls and other commands. Notably, the file system need not be constrained to internally use 512-byte blocks. The option was added as a compromise measure. It was agreed by the standard developers that 512 bytes was the best default unit because of its complete historical consistency on System V (versus the mixed 512/1024-byte usage on BSD systems), and that a option to switch to 1024-byte units was a good compromise. Users who prefer the more logical 1024-byte quantity can use alias to map to without b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unix File Types
The Unix file types are the categories of file formats that a Unix-based system uses to provide context-sensitive behavior of file system items all of which called ''files'' in Unix-based systems. POSIX defines categories: regular, Directory (computing), directory, symbolic link, Named pipe, FIFO special, Device file, block special, character special, and Unix domain socket, socket. An operating system may define additional categories (e.g. Solaris Doors (computing), doors). A regular file is any file format that the file system does not know and relies on applications to manipulate. The other categories are for file formats that the file system inherently knows and can manipulate. The ls, ls -l command reports a file's category via the character before the File-system permissions#Notation of traditional Unix permissions, permissions information. The File (command), file command reports file format information; even for regular files. Representations Numeric The type of a f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mkdir
(make directory) command (computing), command in the Unix, DOS, Digital Research, DR FlexOS, IBM OS/2, Microsoft Windows, and ReactOS operating systems is used to make a new directory (file systems), directory. It is also available in the Unified Extensible Firmware Interface, EFI shell and in the PHP scripting language. In DOS, OS/2, Windows and ReactOS, the command is often abbreviated to md. The command is analogous to the Stratus Technologies, Stratus Stratus VOS, OpenVOS create_dir command. MetaComCo TRIPOS and AmigaDOS provide a similar MakeDir command to create new directories. The numerical analysis, numerical computing environments MATLAB and GNU Octave include an mkdir function with similar functionality. History In early versions of Unix (Berkeley Software Distribution, 4.1BSD and early versions of System V), this command had to be setuid superuser, root as the kernel (operating system), kernel did not have an mkdir syscall. Instead, it made the directory with mknod a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ln (Unix)
is a shell command for creating a link file to an existing file or directory. By default, the command creates a hard link, but with the command line option, it creates a symbolic link. Most systems disallow a hard link to a directory since such links could disrupt the structure of a file system and interfere with the operation of other utilities. The command can create a symbolic link to non-existent file. The command appeared in Issue 2 of the X/Open Portability Guidelines. The version in GNU Core Utilities was written by Mike Parker and David MacKenzie. The command is available in Windows via UnxUtils and has been ported to IBM i. Links A link allows more than one path to refer to the same file. A hard link is a directory entry that refers to a file's inode (an internal reference). A file can have multiple hard links each referring to the same inode. Creating a hard link does not copy the contents of the file; but merely causes another name to be associated with the sam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cp (Unix)
cp is a shell command for copying files and directories. If the user has write access to a target file, the command copies the content by opening it in update mode. This preserves the file's inode instead of creating a new file with default permissions. The command was part of Version 1 Unix, and is specified by POSIX. The implementation from GNU has many additional options beyond the POSIX specification. The command is bundled in GNU Core Utilities and is available in the EFI shell. Options *-f (force) – specifies removal of each target file if it cannot be opened for write operations; removal precedes any copying * -H (dereference) – follows symbolic link In computing, a symbolic link (also symlink or soft link) is a file whose purpose is to point to a file or directory (called the "target") by specifying a path thereto. Symbolic links are supported by POSIX and by most Unix-like operating syste ...s so that the destination has the target file rather ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GNU Project
The GNU Project ( ) is a free software, mass collaboration project announced by Richard Stallman on September 27, 1983. Its goal is to give computer users freedom and control in their use of their computers and Computer hardware, computing devices by collaboratively developing and publishing software that gives everyone the rights to freely run the software, copy and distribute it, study it, and modify it. GNU software grants these rights in GNU General Public License, its license. In order to ensure that the ''entire'' software of a computer grants its users all freedom rights (use, share, study, modify), even the most fundamental and important part, the operating system (including all its numerous utility programs) needed to be free software. Stallman decided to call this operating system ''GNU'' (a recursive acronym meaning "''GNU's not Unix!''"), basing its design on that of Unix, a proprietary operating system. According to its manifesto, the founding goal of the project w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chgrp
, short for change group, is a shell command for changing the group associated with a Unix-based file system file including special files such as directories. Changing the group of a file is restricted to a super-user (such as via ) or to the file's owning user if the user is in the specified group. A file has access permissions for the owning user, a group and for others. Changing the group for a file changes access to it based on users' group memberships. History The command was originally developed as part of the Unix operating system by AT&T Bell Laboratories. It is available in most Unix-like systems, Plan 9, Inferno and IBM i. The version of chgrp bundled in GNU coreutils was written by David MacKenzie. Use Generally, the syntax can be described as: chgrp 'options''''group'' ''files'' * ''group'' specifies the group with which the files should be associated; may be either a symbolic name or an identifier An identifier is a name that identifies (that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GNU General Public License
The GNU General Public Licenses (GNU GPL or simply GPL) are a series of widely used free software licenses, or ''copyleft'' licenses, that guarantee end users the freedom to run, study, share, or modify the software. The GPL was the first copyleft license available for general use. It was originally written by Richard Stallman, the founder of the Free Software Foundation (FSF), for the GNU Project. The license grants the recipients of a computer program the rights of the Free Software Definition. The licenses in the GPL series are all copyleft licenses, which means that any derivative work must be distributed under the same or equivalent license terms. The GPL is more restrictive than the GNU Lesser General Public License, and even more distinct from the more widely used permissive software licenses such as BSD, MIT, and Apache. Historically, the GPL license family has been one of the most popular software licenses in the free and open-source software (FOSS) domai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mktemp
mktemp is a command available in many Unix-like operating systems that creates a temporary file or directory. Originally released in 1997 as part of OpenBSD 2.1, a separate implementation exists as a part of GNU Coreutils. There used to be a similar named C library function, which is now deprecated for being unsafe, and has safer alternatives. See also * Filesystem Hierarchy Standard * Temporary folder * TMPDIR * Unix filesystem In Unix and operating systems inspired by it, the file system is considered a central component of the operating system. It was also one of the first parts of the system to be designed and implemented by Ken Thompson in the first experimental ... References Unix software 1997 software {{unix-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chown
, short for change owner, is a shell command for changing the owning user of Unix-based file system files including special files such as directories. The ownership of a file may only be altered by a super-user (such as via sudo). A regular user cannot ''give away'' their ownership of a file. The version of chown bundled in GNU coreutils was written by David MacKenzie and Jim Meyering. The command is available for Windows Windows is a Product lining, product line of Proprietary software, proprietary graphical user interface, graphical operating systems developed and marketed by Microsoft. It is grouped into families and subfamilies that cater to particular sec ... via UnxUtils. The command was ported to IBM i. See also * * * * References https://en.m.wikipedia.org/wiki/Chown# External links * chown manual pageby The Linux Information Project (LINFO) {{Core Utilities commands Operating system security Standard Unix programs Unix SUS2008 utilit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
