Split (Unix)
split is a utility on Unix, Plan 9, and Unix-like operating systems most commonly used to split a computer file into two or more smaller files. History The command first appeared in Version 3 Unix and is part of the X/Open Portability Guide since issue 2 of 1987. It was inherited into the first version of POSIX.1 and the Single Unix Specification. The version of split bundled in GNU coreutils was written by Torbjorn Granlund and Richard Stallman. The command has also been ported to the IBM i operating system. Usage The command-syntax is: split PTION NPUT [PREFIX The default behavior of split is to generate output files of a fixed size, default 1000 lines. The files are named by appending ''aa'', ''ab'', ''ac'', etc. to ''output filename''. If ''output filename'' is not given, the default filename of ''x'' is used, for example, ''xaa'', ''xab'', etc. When a hyphen (''-'') is used instead of ''input filename'', data is derived from standard input. The files are typically ... [...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] |
![]() |
Ancient Unix
Ancient history is a time period from the beginning of writing and recorded human history through late antiquity. The span of recorded history is roughly 5,000 years, beginning with the development of Sumerian cuneiform script. Ancient history covers all continents inhabited by humans in the period 3000 BCAD 500, ending with the expansion of Islam in late antiquity. The three-age system periodises ancient history into the Stone Age, the Bronze Age, and the Iron Age, with recorded history generally considered to begin with the Bronze Age. The start and end of the three ages vary between world regions. In many regions the Bronze Age is generally considered to begin a few centuries prior to 3000 BC, while the end of the Iron Age varies from the early first millennium BC in some regions to the late first millennium AD in others. During the time period of ancient history, the world population was exponentially increasing due to the Neolithic Revolution, which was in full prog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
![]() |
Unix SUS2008 Utilities
Unix (, ; trademarked as UNIX) is a family of multitasking, multi-user computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, and others. Initially intended for use inside the Bell System, AT&T licensed Unix to outside parties in the late 1970s, leading to a variety of both academic and commercial Unix variants from vendors including University of California, Berkeley ( BSD), Microsoft (Xenix), Sun Microsystems (SunOS/ Solaris), HP/ HPE ( HP-UX), and IBM ( AIX). The early versions of Unix—which are retrospectively referred to as " Research Unix"—ran on computers such as the PDP-11 and VAX; Unix was commonly used on minicomputers and mainframes from the 1970s onwards. It distinguished itself from its predecessors as the first portable operating system: almost the entire operating system is written in the C programming language (in 1973), which allows Un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Standard Unix Programs
Standard may refer to: Symbols * Colours, standards and guidons, kinds of military signs * Heraldic flag, Standard (emblem), a type of a large symbol or emblem used for identification Norms, conventions or requirements * Standard (metrology), an object that bears a defined relationship to a unit of measure used for calibration of measuring devices * Standard (timber unit), an obsolete measure of timber used in trade * Breed standard (also called bench standard), in animal fancy and animal husbandry * BioCompute Object, BioCompute Standard, a standard for next generation sequencing * De facto standard, ''De facto'' standard, product or system with market dominance * Gold standard, a monetary system based on gold; also used metaphorically for the best of several options, against which the others are measured * Internet Standard, a specification ratified as an open standard by the Internet Engineering Task Force * Learning standards, standards applied to education content * Stand ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
|
List Of Unix Commands
This is a list of the shell commands of the most recent version of the Portable Operating System Interface (POSIX) IEEE Std 1003.1-2024 which is part of the Single UNIX Specification (SUS). These commands are implemented in many shells on modern Unix, Unix-like and other operating systems. This list does not cover commands for all versions of Unix and Unix-like shells nor other versions of POSIX. See also * GNOME Core Applications * GNU Core Utilities * List of GNU packages * List of KDE applications * List of Unix daemons * Unix philosophy The Unix philosophy, originated by Ken Thompson, is a set of cultural norms and philosophical approaches to Minimalism (computing), minimalist, Modularity (programming), modular software development. It is based on the experience of leading devel ... * References External links IEEE Std 1003.1,2004 specificationsIEEE Std 1003.1,2008 specificationsIEEE Std 1003.1,2024 specifications– configurable list of equivalent pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
|
File Spanning
{{Redir, Binary spanning, the mathematical optimization method, Binary splitting File spanning is the ability to package a single file or data stream into separate files of a specified size. This task implies the ability to re-combine the package files back into the original file or data stream. This is useful when saving large files onto smaller volumes or breaking large files up into smaller files for network messages of limited size (email, newsgroups). It also allows the creation of parity files such as parchive (PAR) to verify and restore missing or corrupted package files. Another advantage with this is coping with file size limits on some file systems of removable media, or coping with volume size limits of things like floppy disks. Sometimes the file spanning process is hidden as a secondary operation such as with file archivers. In this case, many smaller files are first packaged into a data stream and then repackaged into a multi-file archive. File spanning softwar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
|
Csplit
The csplit command in Unix and Unix-like operating systems is a utility that is used to split a file into two or more smaller files determined by context lines. History csplit is part of the X/Open Portability Guide since issue 2 of 1987. It was inherited into the first version of POSIX and the Single Unix Specification. It first appeared in PWB UNIX. The version of csplit bundled in GNU coreutils was written by Stuart Kemp and David MacKenzie. The command is available as a separate package for Microsoft Windows as part of the UnxUtils collection of native Win32 ports of common GNU Unix-like utilities. Usage The command-syntax is: csplit PTION.. FILE PATTERN... The ''patterns'' may be line numbers or regular expressions. The program outputs pieces of the file separated by the patterns into files xx00, xx01, etc., and outputs the size of each piece, in bytes, to standard output. The ''optional parameters'' modify the behaviour of the program in various ways. For example, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
|
Cat (Unix)
cat is a shell command for writing the content of a file or input stream to standard output. The name is an abbreviation of ''concatenate'' which is from the Latin ''catenare'' meaning "to chain" Originally developed for Unix, it is available on many operating systems and shells today. In addition to combining files, cat is commonly used to copy files and in particular to copy a file to the terminal monitor. Unless re-directed, outputs file content on-screen. History cat was part of the early versions of Unix, e.g., Version 1. It replaced pr, a PDP-7 and Multics command for copying a single file to the screen. It was written by Ken Thompson and Dennis Ritchie. The implementation of cat bundled in GNU coreutils was written by Torbjorn Granlund and Richard Stallman. The ReactOS implementation was written by David Welch, Semyon Novikov, and Hermès Bélusca. Over time, alternative utilities such as tac and bat also became available, bringing different new features. Use ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
|
Standard Input
In computer programming, standard streams are preconnected input and output communication channels between a computer program and its environment when it begins execution. The three input/output (I/O) connections are called standard input (stdin), standard output (stdout) and standard error (stderr). Originally I/O happened via a physically connected system console (input via keyboard, output via monitor), but standard streams abstract this. When a command is executed via an interactive shell, the streams are typically connected to the text terminal on which the shell is running, but can be changed with redirection or a pipeline. More generally, a child process inherits the standard streams of its parent process. Application Users generally know standard streams as input and output channels that handle data coming from an input device, or that write data from the application. The data may be text with any encoding, or binary data. When a program is run as a daemon, its standard ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
|
Syntax
In linguistics, syntax ( ) is the study of how words and morphemes combine to form larger units such as phrases and sentences. Central concerns of syntax include word order, grammatical relations, hierarchical sentence structure (constituency), agreement, the nature of crosslinguistic variation, and the relationship between form and meaning (semantics). Diverse approaches, such as generative grammar and functional grammar, offer unique perspectives on syntax, reflecting its complexity and centrality to understanding human language. Etymology The word ''syntax'' comes from the ancient Greek word , meaning an orderly or systematic arrangement, which consists of (''syn-'', "together" or "alike"), and (''táxis'', "arrangement"). In Hellenistic Greek, this also specifically developed a use referring to the grammatical order of words, with a slightly altered spelling: . The English term, which first appeared in 1548, is partly borrowed from Latin () and Greek, though the L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
|
![]() |
Richard Stallman
Richard Matthew Stallman ( ; born March 16, 1953), also known by his initials, rms, is an American free software movement activist and programmer. He campaigns for software to be distributed in such a manner that its users have the freedom to use, study, distribute, and modify that software. Software which ensures these freedoms is termed free software. Stallman launched the GNU Project, founded the Free Software Foundation (FSF) in October 1985, developed the GNU Compiler Collection and GNU Emacs, and wrote all versions of the GNU General Public License. Stallman launched the GNU Project in September 1983 to write a Unix-like computer operating system composed entirely of free software. With that he also launched the free software movement. He has been the GNU project's lead architect and organizer, and developed a number of pieces of widely used GNU software including among others, the GNU Compiler Collection, GNU Debugger, and GNU Emacs text editor. Stallman pioneered the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GNU 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 Changes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |