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Find (Unix)
In Unix-like operating systems, find is a command-line utility that locates files based on some user-specified criteria and either prints the pathname of each matched object or, if another action is requested, performs that action on each matched object. It initiates a search from a desired starting location and then recursively traverses the nodes (directories) of a hierarchical structure (typically a tree). find can traverse and search through different file systems of partitions belonging to one or more storage devices mounted under the starting directory. The possible search criteria include a pattern to match against the filename or a time range to match against the modification time or access time of the file. By default, find returns a list of all files below the current working directory, although users can limit the search to any desired maximum number of levels under the starting directory. The related locate programs use a database of indexed files obtained thro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AT&T Bell Laboratories
Nokia Bell Labs, commonly referred to as ''Bell Labs'', is an American industrial research and development company owned by Finnish technology company Nokia. With headquarters located in Murray Hill, New Jersey, Murray Hill, New Jersey, the company operates several laboratories in the United States and around the world. As a former subsidiary of the American Telephone and Telegraph Company (AT&T), Bell Labs and its researchers have been credited with the development of radio astronomy, the transistor, the laser, the photovoltaic cell, the charge-coupled device (CCD), information theory, the Unix operating system, and the programming languages B (programming language), B, C (programming language), C, C++, S (programming language), S, SNOBOL, AWK, AMPL, and others, throughout the 20th century. Eleven Nobel Prizes and five Turing Awards have been awarded for work completed at Bell Laboratories. Bell Labs had its origin in the complex corporate organization of the Bell System telepho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cron
The cron command-line utility is a job scheduler on Unix-like operating systems. Users who set up and maintain software environments use cron to schedule jobs (commands or shell scripts), also known as cron jobs, to run periodically at fixed times, dates, or intervals. It typically automates system maintenance or administration—though its general-purpose nature makes it useful for things like downloading files from the Internet and downloading email at regular intervals. Cron is most suitable for scheduling repetitive tasks. Scheduling one-time tasks can be accomplished using the associated ''at'' utility. Cron's name originates from Chronos, the Greek word for time. Overview The actions of cron are driven by a crontab (cron table) file, a configuration file that specifies shell commands to run periodically on a given schedule. The crontab files are stored where the lists of jobs and other instructions to the cron daemon are kept. Users can have their own individual cr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 systems, such as FreeBSD, Linux, and macOS. Support also exists in Windows 10 and 11. CTSS on IBM 7090 had files linked by name in 1963. By 1978 minicomputer operating systems from DEC, and in Data General's RDOS included symbolic links. Overview A symbolic link contains a text string that is automatically interpreted and followed by the operating system as a path to another file or directory. This other file or directory is called the "target". The symbolic link is a second file that exists independently of its target. If a symbolic link is deleted, its target remains unaffected. If a symbolic link points to a target, and sometime later that target is moved, renamed or deleted, the symbolic link is not automatically updated or deleted, b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Regular File
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, symbolic link, FIFO special, block special, character special, and socket. An operating system may define additional categories (e.g. Solaris 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 -l command reports a file's category via the character before the permissions information. The file command reports file format information; even for regular files. Representations Numeric The type of a file is specified by the file's mode, which consists of the file type and access permissions. The stat() system call returns information about a file in a structure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Directory (computing)
In computing, a directory is a file system cataloging structure that contains references to other computer files, and possibly other directories. On many computers, directories are known as folders or drawers, analogy, analogous to a workbench or the traditional office filing cabinet. The name derives from books like a telephone directory that lists the phone numbers of all the people living in a certain area. Files are organized by storing related files in the same directory. In a hierarchical file system (that is, one in which files and directories are organized in a manner that resembles a tree structure, tree), a directory contained inside another directory is called a subdirectory. The terms parent and child are often used to describe the relationship between a subdirectory and the directory in which it is cataloged, the latter being the parent. The top-most directory in such a filesystem, which does not have a parent of its own, is called the root directory. The freedesktop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Device File
In Unix-like operating systems, a device file, device node, or special file is an interface to a device driver that appears in a file system as if it were an ordinary file. There are also special files in DOS, OS/2, and Windows. These special files allow an application program to interact with a device by using its device driver via standard input/output system calls. Using standard system calls simplifies many programming tasks, and leads to consistent user-space I/O mechanisms regardless of device features and functions. Overview Device files usually provide simple interfaces to standard devices (such as printers and serial ports), but can also be used to access specific unique resources on those devices, such as disk partitions. Additionally, device files are useful for accessing system resources that have no connection with any actual device, such as data sinks and random number generators. There are two general kinds of device files in Unix-like operating syst ... [...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] |
Command-line Argument
A command-line interface (CLI) is a means of interacting with software via command (computing), commands each formatted as a line of text. Command-line interfaces emerged in the mid-1960s, on computer terminals, as an interactive and more user-friendly alternative to the non-interactive mode available with punched cards. For a long time, a CLI was the most common interface for software, but today a graphical user interface (GUI) is more common. Nonetheless, many programs such as operating system and software development utility software, utilities still provide CLI. A CLI enables automation, automating computer program, programs since commands can be stored in a scripting language, script computer file, file that can be used repeatedly. A script allows its contained commands to be executed as group; as a program; as a command. A CLI is made possible by command-line interpreters or command-line processors, which are programs that execute input commands. Alternatives to a CLI ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glob (programming)
glob() () is a libc function for ''globbing'', which is the archetypal use of pattern matching against the names in a filesystem directory such that a name pattern is expanded into a list of names matching that pattern. Although ''globbing'' may now refer to glob()-style pattern matching of any string, not just expansion into a list of filesystem names, the original meaning of the term is still widespread. The glob() function and the underlying gmatch() function originated at Bell Labs in the early 1970s alongside the original AT&T UNIX itself and had a formative influence on the syntax of UNIX command line utilities and therefore also on the present-day reimplementations thereof. In their original form, glob() and gmatch() derived from code used in Bell Labs in-house utilities that developed alongside the original Unix in the early 1970s. Among those utilities were also two command line tools called glob and find; each could be used to pass a list of matching filenames to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wildcard Character
In software, a wildcard character is a kind of placeholder represented by a single character (computing), character, such as an asterisk (), which can be interpreted as a number of literal characters or an empty string. It is often used in file searches so the full name need not be typed. Telecommunication In telecommunications, a wildcard is a character that may be substituted for any of a defined subset of all possible characters. * In high-frequency (HF) radio automatic link establishment, the wildcard character may be substituted for any one of the 36 upper-case alphanumeric characters. * Whether the wildcard character represents a single character or a String (computer science), string of characters must be specified. Computing In computer (software) technology, a wildcard is a symbol used to replace or represent zero or more characters. Matching wildcards, Algorithms for matching wildcards have been developed in a number of recursion, recursive and non-recursive varietie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GNU Find Utilities
A number of notable software packages were developed for, or are maintained by, the Free Software Foundation as part of the GNU Project. General aspects of GNU packages Summarising the situation in 2013, Richard Stallman identified nine aspects which generally apply to being a GNU package, but he noted that exceptions and flexibility are possible when there are good reasons: # The package should say that it is a GNU package. # It should be distributed via ftp.gnu.org, or another site offering access to everyone. # The package's homepage should be on the GNU website. # The developers must pay attention to making their software work well with other GNU packages. # Documentation should be in Texinfo format, or in a format easily convertible to Texinfo. # Should use GNU Guile for its extension language, but exceptions are explicitly possible in this regard. # Should not recommend any non-free program, nor refer the user to any non-free documentation or non-free software. # Use GNU ter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
