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Version Control Systems
Version control (also known as revision control, source control, and source code management) is the software engineering practice of controlling, organizing, and tracking different versions in history of computer files; primarily source code text files, but generally any type of file. Version control is a component of software configuration management. A ''version control system'' is a software tool that automates version control. Alternatively, version control is embedded as a feature of some systems such as word processors, spreadsheets, collaborative web docs, and content management systems, e.g., Wikipedia's page history. Version control includes viewing old versions and enables reverting a file to a previous version. Overview As teams develop software, it is common to deploy multiple versions of the same software, and for different developers to work on one or more different versions simultaneously. Bugs or features of the software are often only present in cer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Software Engineering
Software engineering is a branch of both computer science and engineering focused on designing, developing, testing, and maintaining Application software, software applications. It involves applying engineering design process, engineering principles and computer programming expertise to develop software systems that meet user needs. The terms ''programmer'' and ''coder'' overlap ''software engineer'', but they imply only the construction aspect of a typical software engineer workload. A software engineer applies a software development process, which involves defining, Implementation, implementing, Software testing, testing, Project management, managing, and Software maintenance, maintaining software systems, as well as developing the software development process itself. History Beginning in the 1960s, software engineering was recognized as a separate field of engineering. The development of software engineering was seen as a struggle. Problems included software that was over ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abstraction (computer Science)
In software engineering and computer science, abstraction is the process of generalizing concrete details, such as attributes, away from the study of objects and systems to focus attention on details of greater importance. Abstraction is a fundamental concept in computer science and software engineering, especially within the object-oriented programming paradigm. Examples of this include: * the usage of abstract data types to separate usage from working representations of data within programs; * the concept of functions or subroutines which represent a specific way of implementing control flow; * the process of reorganizing common behavior from groups of non-abstract classes into abstract classes using inheritance and sub-classes, as seen in object-oriented programming languages. Rationale Computing mostly operates independently of the concrete world. The hardware implements a model of computation that is interchangeable with others. The software is structured in archit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
File Locking
File locking is a mechanism that restricts access to a computer file, or to a region of a file, by allowing only one user or process to modify or delete it at a specific time, and preventing reading of the file while it's being modified or deleted. Systems implement locking to prevent an ''interceding update'' scenario, which is an example of a race condition, by enforcing the serialization of update processes to any given file. The following example illustrates the interceding update problem: # Process A reads a customer record from a file containing account information, including the customer's account balance and phone number. # Process B now reads the same record from the same file, so it has its own copy. # Process A changes the account balance in its copy of the customer record and writes the record back to the file. # Process B, which still has the original ''stale'' value for the account balance in its copy of the customer record, updates the account balance and writes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Distributed Version Control
In software development, distributed version control (also known as distributed revision control) is a form of version control in which the complete codebase, including its full history, is mirrored on every developer's computer. Compared to centralized version control, this enables automatic management Branching (version control), branching and Merge (version control), merging, speeds up most operations (except pushing and fetching), improves the ability to work offline, and does not rely on a single location for backups. Git (software), Git, the world's most popular version control system, is a distributed version control system. In 2010, software development author Joel Spolsky described distributed version control systems as "possibly the biggest advance in software development technology in the [past] ten years". Distributed vs. centralized Distributed version control systems (DVCS) use a peer-to-peer approach to version control, as opposed to the client–server model, clien ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apache Subversion
Apache Subversion (often abbreviated SVN, after its command name ''svn'') is a version control system distributed as open source under the Apache License. Software developers use Subversion to maintain current and historical versions of files such as source code, web pages, and documentation. Its goal is to be a mostly compatible successor to the widely used Concurrent Versions System (CVS). The open source community has used Subversion widely: for example, in projects such as Apache Software Foundation, FreeBSD, SourceForge, and from 2006 to 2019, GCC. CodePlex was previously a common host for Subversion repositories. Subversion was created by CollabNet Inc. in 2000, and is now a top-level Apache project being built and used by a global community of contributors. History CollabNet founded the Subversion project in 2000 as an effort to write an open-source version-control system which operated much like CVS but which fixed the bugs and supplied some features missing in CVS ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Concurrent Versions System
Concurrent Versions System (CVS, or Concurrent Versioning System) is a version control system originally developed by Dick Grune in July 1986. Design CVS operates as a front end to Revision Control System (RCS), an older version control system that manages individual files but not whole projects. It expands upon RCS by adding support for repository-level change tracking, and a client-server model. Files are tracked using the same history format as in RCS, with a hidden directory containing a corresponding history file for each file in the repository. CVS uses delta compression for efficient storage of different versions of the same file. This works well with large text files with few changes from one version to the next. This is usually the case for source code files. On the other hand, when CVS is told to store a file as binary, it will keep each individual version on the server. This is typically used for non-text files such as executable images where it is difficult ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Revision Control System
Version control (also known as revision control, source control, and source code management) is the software engineering practice of controlling, organizing, and tracking different versions in history of computer files; primarily source code text files, but generally any type of file. Version control is a component of software configuration management. A ''version control system'' is a software tool that automates version control. Alternatively, version control is embedded as a feature of some systems such as word processors, spreadsheets, collaborative web docs, and content management systems, e.g., Wikipedia's page history. Version control includes viewing old versions and enables reverting a file to a previous version. Overview As teams develop software, it is common to deploy multiple versions of the same software, and for different developers to work on one or more different versions simultaneously. Bugs or features of the software are often only present in ce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Source Code Control System
Source Code Control System (SCCS) is a version control system designed to track changes in source code and other text files during the development of a piece of software. This allows the user to retrieve any of the previous versions of the original source code and the changes which are stored. It was originally developed at Bell Labs beginning in late 1972 by Marc Rochkind for an IBM System/370 computer running OS/360. A characteristic feature of SCCS is the ''sccsid'' string that is embedded into source code, and automatically updated by SCCS for each revision. This example illustrates its use in the C programming language: static char sccsid[] = "@(#)ls.c 8.1 (Berkeley) 6/11/93"; This String (computer science), string contains the file name, date, and can also contain a comment. After compilation, the string can be found in binary and object files by looking for the pattern @(#) and can be used to determine which source code files were used during compilation. The wha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Panvalet
Computer Associates Panvalet (also known as CA-Panvalet) is a revision control and source code management system originally developed by Pansophic Systems for mainframe computers such as the IBM System z and IBM System/370 running the z/OS and z/VSE operating systems. CA-PAN/LCM is a similar product for PCs. Overview Panvalet can be used to manage program source code, JCL, Macros/commands for utilities such as Easytrieve and object module files. History Panvalet was developed by Pansophic Systems in 1969 as a program to store and manage computer program source code on direct-access storage devices. Before Panvalet code was saved as paper punch cards, typically with 500 to 3,000 cards per program, often 1,000,000 or more per data center. Cards were bulky, difficult to store and transport, difficult and costly to back up, and prone to catastrophic errors since one misplaced card could prevent a program from running correctly. Pansophic began selling the program in 1970 at a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Librarian (version Control System)
The Librarian is a version control system and source code management software product originally developed by Applied Data Research for IBM mainframe computers. It was designed to supplant physical punched card decks as a way of maintaining programs, but kept a card model in terms of its interface. During the 1970s and 1980s it was in use at thousands of IBM mainframe installations and was one of the best-selling software products in the computer industry. After Applied Data Research was acquired by Computer Associates in 1988, the product became known as CA-Librarian. After that company was acquired by Broadcom in 2018, the product became known simply as Librarian. History Most computer source programs in the 1960s were kept on punched cards, which was problematic due to the amount of physical space they took, the constant chance of card decks being dropped or otherwise damaged, and problems with keeping a history of changes to the program. Even into the mid-to-late 1970s, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Support Programs For OS/360 And Successors
This article discusses support programs included in or available for OS/360 and successors. IBM categorizes some of these programs as utilities and others as service aids; the boundaries are not always consistent or obvious. Many, but not all, of these programs match the types in utility software. The following lists describe programs associated with OS/360 and successors. No DOS, TPF or VM utilities are included. Naming convention IBM uses a naming convention for modules where the first three letters identify the "component" to which a module belongs. In OS/VS, IBM renamed most of the IMx messages as AMx for OS/VS2 and HMx for OS/VS1. History/Common JCL Many of these programs were designed by IBM users, through the group SHARE, and then modified or extended by IBM from versions originally written by a user. These programs are usually invoked via Job Control Language (JCL). They tend to use common JCL DD identifiers (in the OS, now z/OS operating systems) for their data ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apress
Springer Nature or the Springer Nature Group is a German-British academic publishing company created by the May 2015 merger of Springer Science+Business Media and Holtzbrinck Publishing Group's Nature Publishing Group, Palgrave Macmillan, and Macmillan Education. History The company originates from several journals and publishing houses, notably Springer-Verlag, which was founded in 1842 by Julius Springer in Berlin (the grandfather of Bernhard Springer who founded Springer Publishing in 1950 in New York), Nature Portfolio, Nature Publishing Group which has published ''Nature (journal) , Nature'' since 1869, and Macmillan Education, which goes back to Macmillan Publishers founded in 1843. Springer Nature was formed in 2015 by the merger of Nature Publishing Group, Palgrave Macmillan, and Macmillan Education (held by Holtzbrinck Publishing Group) with Springer Science+Business Media (held by BC Partners). Plans for the merger were first announced on 15 January 2015. The transactio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
