DOCSLIB.ORG

Revision Control

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Revision Control Revision Control Tomáš Kalibera, (Peter Libič) Department of Distributed and Dependable Systems http://d3s.mff.cuni.cz CHARLES UNIVERSITY PRAGUE Faculty of Mathematics and Physics Problems solved by revision control What is it good for? Keeping history of system evolution • What a “system” can be . Source code (single file, source tree) . Textual document . In general anything what can evolve – can have versions • Why ? . Safer experimentation – easy reverting to an older version • Additional benefits . Tracking progress (how many lines have I added yesterday) . Incremental processing (distributing patches, …) Allowing concurrent work on a system • Why concurrent work ? . Size and complexity of current systems (source code) require team work • How can concurrent work be organized ? 1. Independent modifications of (distinct) system parts 2. Resolving conflicting modifications 3. Checking that the whole system works . Additional benefits . Evaluating productivity of team members Additional benefits of code revision control • How revision control helps . Code is isolated at one place (no generated files) . Notifications when a new code version is available • Potential applications that benefit . Automated testing • Compile errors, functional errors, performance regressions . Automated building . Backup • Being at one place, the source is isolated from unneeded generated files . Code browsing • Web interface with hyperlinked code Typical architecture Working copy Source code repository (versioned sources) synchronization Basic operations • Check-out . Create a working copy of repository content • Update . Update working copy using repository (both to latest and historical version) • Check-in (Commit) . Propagate working copy back to repository • Diff . Show differences between two versions of source code Simplified usage scenario Source code Check-out or update repository Working 1 copy 2 Modify & Test Check-in 3 Exporting/importing source trees • Import . Importing a whole (presently non-versioned) source tree into a repository • Export . Exporting whole source tree from a repository . Similar to check-out, but the exported tree does not contain metadata that would allow to check-in the changes Branching and merging Main development branching merging Parallel development Time & software versions Why parallel development of different versions • Experimental versions . Isolate intrusive and potentially dangerous experimental development . (1) Branch from latest version . (2) Merge back when stable • Bugfixes . Fix a bug in an older version (already released and considered stable) . (1) Branch from an older version . (2) Merge to main development only if the bug is still there Branching details • Branch root . A given version (of a given branch – branches can be branched) . Typically latest version of a given branch (i.e. main development branch) • May not need a working copy . In principle, branching is an operation performed only on the repository • Naming . Branches typically have symbolic human readable names . They also may be numbered, creating a hierarchical structure of versions Merging details (1) • Merge objective . Merge changes made in two branches of development into one branch . In detail: apply changes made in a branch to the current version of the original branch Main development branching merging Parallel development Diff operation (2-way) • Objective . Compare 2 text (source code) files . Produce brief and concise list of differences • Input . Two textual files, compares 2nd against 1st • Output (line-based diff) . List of added lines, deleted lines, and (sometimes) modified lines . The exact distinction of what is still a modification depends on the algorithm Diff operation (2-way) – Example Diff operation (2-way) – LCS based algorithm 1. View files as lists of lines 2. Find longest common subsequence (LCS) – non-continuous sequence of lines that are present in both files 3. Match lines from the common subsequence 4. Mark the blocks of remaining lines as . Added – iff all its lines are only in the 2nd file . Deleted – iff all its lines are only in the 1st file . Modified – otherwise Diff (2-way) applications • Incremental data representation . Backup (binary files use a different algorithm) . Internal storage format in revision control system . Distribution of sources in form of patches • Visual help for programmers . Graphical representation of what has been changed Back to merging – 3-way merge operation A Modified version Common ancestor O B Modified version 1. Two-way diff of A and O (finding LCS suffices) 2. Two-way diff of B and O (finding LCS suffices) 3. Resulting blocks of lines are • Left alone – iff equal in all versions O,A,B • Automatically changed – iff changed only in A or B • Left for manual fix – otherwise (CONFLICT) Merging summary • Merge objective . Synchronize changes made in parallel • Typical merge usage 1. Invoke merge explicitly (merging branches) or implicitly (checking-in in case of concurrent changes) 2. Resolve conflicts – some have to be resolved manually, all should be checked 3. Check-in the merged sources Synchronizing the developers • Why in revision control system ? . Software is developed in teams that may not be always able to communicate directly • Lock-Modify-Unlock solution . Mandatory locking prior to modification • Copy-Modify-Merge . Concurrent modification, resolving conflicts if they happen Lock-Modify-Unlock model • Pros . Conflicts cannot happen (safety) – though depends on locking granularity . Simpler allocation of responsibility • Cons . The sense of safety can be false, if the locking granularity is too fine-grained . Unnecessary serialization, especially when the locking granularity is too coarse-grained . People forget to unlock Copy-Modify-Merge model • In-line with merging of branches • Typical advise: Merge often . Lower chance of conflicts . Smaller conflicts are easier to resolve . More steps of conflict resolution are under versioning control (and can be reviewed) . In-line with “check-in often” – checking in often increases the chance that someone else will have to do the merge… • Merge often is often applied to branches as well Combining the models (Locking and Merging) • A system can support both, allowing users to lock files, but not forcing them to • Locking may not be that strict . Users can break them (not needing to contact the administrator) • Watches . Users can register to receive notifications when a particular file is used by someone else (locked, modified, … - depending on the system) Existing versioning systems (selected) • SCCS (Source Code Control System) . Marc Rochkind, Bell Labs, 1972, UNIX . Works on single files, now obsolete • RCS (Revision Control System) . Walter Tichy, Purdue Uni, 1980, GNU . Works on single files . Simple installation (repository files are typically kept next to the working copy) . RCS repository file format for storing multiple revisions of a text file is still used (CVS, TWiki) Existing versioning systems (selected) • CVS (Concurrent Versioning System) . Dick Grune, 1986, Brian Berliner, 1989, free . Uses RCS, allows operation on multiple files . Many big projects were using CVS, but the trend is moving towards newer systems • i.e. Mozilla -> Mercurial, GIMP -> git • SVN (Subversion) . ~2000, CollabNet team, free; Apache project now . Intended as CVS replacement . Easier to use than CVS, support for binary files, versioning of directories . Currently used by many open-source projects (i.e. Apache, GCC), but many are moving towards distributed systems (i.e. KDE -> git) Existing versioning systems (selected) • ClearCase . Atria Software, 1992, now IBM, commercial . Special versioned filesystem, views . Excessively complex to use . Used by Arpege/Aladin numerical weather forecast model Existing versioning systems (selected) • Mercurial • Bazaar • GIT . Linus Torvalds, 2005 . Distributed repository . Used by Linux Kernel.
Load more

Recommended publications
  • Version Control – Agile Workflow with Git/Github
    Version Control – Agile Workflow with Git/GitHub 19/20 November 2019 | Guido Trensch (JSC, SimLab Neuroscience) Content Motivation Version Control Systems (VCS) Understanding Git GitHub (Agile Workflow) References Forschungszentrum Jülich, JSC:SimLab Neuroscience 2 Content Motivation Version Control Systems (VCS) Understanding Git GitHub (Agile Workflow) References Forschungszentrum Jülich, JSC:SimLab Neuroscience 3 Motivation • Version control is one aspect of configuration management (CM). The main CM processes are concerned with: • System building • Preparing software for releases and keeping track of system versions. • Change management • Keeping track of requests for changes, working out the costs and impact. • Release management • Preparing software for releases and keeping track of system versions. • Version control • Keep track of different versions of software components and allow independent development. [Ian Sommerville,“Software Engineering”] Forschungszentrum Jülich, JSC:SimLab Neuroscience 4 Motivation • Keep track of different versions of software components • Identify, store, organize and control revisions and access to it • Essential for the organization of multi-developer projects is independent development • Ensure that changes made by different developers do not interfere with each other • Provide strategies to solve conflicts CONFLICT Alice Bob Forschungszentrum Jülich, JSC:SimLab Neuroscience 5 Content Motivation Version Control Systems (VCS) Understanding Git GitHub (Agile Workflow) References Forschungszentrum Jülich,
    [Show full text]
  • FAKULTÄT FÜR INFORMATIK Leveraging Traceability Between Code and Tasks for Code Reviews and Release Management
    FAKULTÄT FÜR INFORMATIK DER TECHNISCHEN UNIVERSITÄT MÜNCHEN Master’s Thesis in Informatics Leveraging Traceability between Code and Tasks for Code Reviews and Release Management Jan Finis FAKULTÄT FÜR INFORMATIK DER TECHNISCHEN UNIVERSITÄT MÜNCHEN Master’s Thesis in Informatics Leveraging Traceability between Code and Tasks for Code Reviews and Release Management Einsatz von Nachvollziehbarkeit zwischen Quellcode und Aufgaben für Code Reviews und Freigabemanagement Author: Jan Finis Supervisor: Prof. Bernd Brügge, Ph.D. Advisors: Maximilian Kögel, Nitesh Narayan Submission Date: May 18, 2011 I assure the single-handed composition of this master’s thesis only supported by declared resources. Sydney, May 10th, 2011 Jan Finis Acknowledgments First, I would like to thank my adviser Maximilian Kögel for actively supporting me with my thesis and being reachable for my frequent issues even at unusual times and even after he left the chair. Furthermore, I would like to thank him for his patience, as the surrounding conditions of my thesis, like me having an industrial internship and finishing my thesis abroad, were sometimes quite impedimental. Second, I want to thank my other adviser Nitesh Narayan for helping out after Max- imilian has left the chair. Since he did not advise me from the start, he had more effort working himself into my topic than any usual adviser being in charge of a thesis from the beginning on. Third, I want to thank the National ICT Australia for providing a workspace, Internet, and library access for me while I was finishing my thesis in Sydney. Finally, my thanks go to my supervisor Professor Bernd Brügge, Ph.D.
    [Show full text]
  • Distributed Revision Control with Mercurial
    Distributed revision control with Mercurial Bryan O’Sullivan Copyright c 2006, 2007 Bryan O’Sullivan. This material may be distributed only subject to the terms and conditions set forth in version 1.0 of the Open Publication License. Please refer to Appendix D for the license text. This book was prepared from rev 028543f67bea, dated 2008-08-20 15:27 -0700, using rev a58a611c320f of Mercurial. Contents Contents i Preface 2 0.1 This book is a work in progress ...................................... 2 0.2 About the examples in this book ..................................... 2 0.3 Colophon—this book is Free ....................................... 2 1 Introduction 3 1.1 About revision control .......................................... 3 1.1.1 Why use revision control? .................................... 3 1.1.2 The many names of revision control ............................... 4 1.2 A short history of revision control .................................... 4 1.3 Trends in revision control ......................................... 5 1.4 A few of the advantages of distributed revision control ......................... 5 1.4.1 Advantages for open source projects ............................... 6 1.4.2 Advantages for commercial projects ............................... 6 1.5 Why choose Mercurial? .......................................... 7 1.6 Mercurial compared with other tools ................................... 7 1.6.1 Subversion ............................................ 7 1.6.2 Git ................................................ 8 1.6.3
    [Show full text]
  • Source Code Revision Control Systems and Auto-Documenting
    Source Code Revision Control Systems and Auto-Documenting Headers for SAS® Programs on a UNIX or PC Multiuser Environment Terek Peterson, Alliance Consulting Group, Philadelphia, PA Max Cherny, Alliance Consulting Group, Philadelphia, PA ABSTRACT This paper discusses two free products available on UNIX and PC RCS, which is a more powerful utility than SCCS, was written in environments called SCCS (Source Code Control System) and early 1980s by Walter F. Tichy at Purdue University in Indiana. It RCS (Revision Control System). When used in a multi-user used many programs developed in the 1970s, learning from environment, these systems give programmers a tool to enforce mistakes of SCCS and can be seen as a logical improvement of change control, create versions of programs, document changes SCCS. Since RCS stores the latest version in full, it is much to programs, create backups during reporting efforts, and faster in retrieving the latest version. RCS is also faster than automatically update vital information directly within a SASâ SCCS in retrieving older versions and RCS has an easier program. These systems help to create an audit trail for interface for first time users. RCS commands are more intuitive programs as required by the FDA for a drug trial. than SCCS commands. In addition, there are less commands, the system is more consistent and it has a greater variety of options. Since RCS is a newer, more powerful source code INTRODUCTION control system, this paper will primarily focus on that system. The pharmaceutical industry is one of the most regulated industries in this country. Almost every step of a clinical trial is subject to very strict FDA regulations.
    [Show full text]
  • INF5750/9750 - Lecture 1 (Part III) Problem Area
    Revision control INF5750/9750 - Lecture 1 (Part III) Problem area ● Software projects with multiple developers need to coordinate and synchronize the source code Approaches to version control ● Work on same computer and take turns coding ○ Nah... ● Send files by e-mail or put them online ○ Lots of manual work ● Put files on a shared disk ○ Files get overwritten or deleted and work is lost, lots of direct coordination ● In short: Error prone and inefficient The preferred solution ● Use a revision control system. RCS - software that allows for multiple developers to work on the same codebase in a coordinated fashion ● History of Revision Control Systems: ○ File versioning tools, e.g. SCCS, RCS ○ Central Style - tree versioning tools. e.g. CVS ○ Central Style 2 - tree versioning tools e.g. SVN ○ Distributed style - tree versioning tools e.g. Bazaar ● Modern DVCS include Git, Mercurial, Bazaar Which system in this course? ● In this course we will be using GIT as the version control system ● We will use the UIO git system, but you can also make git accounts on github.com or bitbucket for your own projects ● DHIS2 uses a different system: Launchpad/Bazaar How it works Working tree: Local copy of the source code Repository: residing on the Central storage of developer’s the source code at computer (a client) a server synchronize synchronize Commit Commit locally Centralized De-centralized The repository Central ● Remembers every change ever written to it (called commits) ● You can have a central or local repository. ○ Central = big server in
    [Show full text]
  • Simple Version Control of SAS Programs and SAS Data Sets Magnus Mengelbier, Limelogic Ltd, United Kingdom
    Simple Version Control of SAS Programs and SAS Data Sets Magnus Mengelbier, Limelogic Ltd, United Kingdom ABSTRACT SUBVERSION AND LIFE SCIENCES SAS data sets and programs that reside on the local network are most often stored using a simple Subversion can fit very well within Life Sciences and with a tweak here and there, the version and file system with no capability of version control, audit trail of changes and all the benefits. We revision control can be a foundation for a standard and compliant analytics environment and consider the possibility to capitalise on the capabilities of Subversion and other simple process. straightforward conventions to provide version control and an audit trail for SAS data sets, standard macro libraries and programs without changing the SAS environment. TRUNK –BRANCHES –TAGS OR DEV –QC -PROD INTRODUCTION The approach with trunk, branches and tags can also be used within reporting clinical trials, if outputs are standardized for a specific study and used in multiple reporting events. Most organisations will use the benefits of a local network drive, a mounted share or a dedicated SAS server file system to store and archive study data in multiple formats, analytical programs and trunk Pre-lock data and programs for reporting purposes their respective logs, outputs and deliverables. branch Deliverables for a specific reporting event such as Investigator Brochure A manual process is most often implemented to retain versions and snapshots of data, programs (IB), Investigational New Drug (IND), Clinical Study Reports (CSRs), etc and deliverables with varying degrees of success most often. Although not perfect, the process is tag Dry run, Database Lock, Draft Outputs, Final Outputs sufficient to a degree.
    [Show full text]
  • Tech Talk - Devops – a New Software Development Paradigm
    Tech Talk - Devops – a New Software Development Paradigm June 23, 2015 DevOps Exploiting the natural tension between Development & Operations Development Operations Collaboration & Orchestration DevOps a methodology of software development that emphasizes communication, collaboration and integration between software developers and operations personnel. a response to the interdependence of software development and IT operations. It aims to help an organization rapidly produce software products and services DevOps History (per Wikipedia) At the Agile 2008 conference, Andrew Clay Shafer and Patrick Debois discussed "Agile Infrastructure", afterwards creating the Agile System Administrators Group on Google. The term "DevOps" was popularized through a series of "DevOps Days" starting in 2009 in Belgium. Since then, there have been DevOps Days conferences held in many countries worldwide. A DevOps Functional Definition Agile Methods applied to Software Engineering DevOps requires a Lean practice Maximizing customer value while minimizing waste. The goal is to provide perfect value to the customer through a perfect value creation process that has zero waste. If an effort doesn’t add value, don’t do it. DevOps Simplified Phases Release Configuration Management Orchestration . Continuous Integration/Continuous Delivery Monitoring DevOps vs traditional Agile Devops = Agile + Process Rhythm DevOps Getting Started Tools Inventory Skills Assessment Task to be accomplished Tool Selection (there are many more tools than can be used!) Assignment of Responsibility DevOps should be language neutral, although modern languages popular today are: Java, Ruby, Python, C++,… DevOps lifecycle – (New Relic) • Create new code changes • Check in code • Pull code changes, check latest patches, and build • Test (continuous integration server to generate builds & arrange releases): • individual models • integration tests • user acceptance tests.
    [Show full text]
  • Revision Control Solutions to Protect Your Documents and Track Workflow
    Revision Control Solutions to Protect Your Documents and Track Workflow WHITE PAPER Contents Overview 3 Common Revision Control Systems 4 Revision Control Systems 4 Using BarTender with Revision Control Systems 4 Limitations of Windows Security 5 Librarian 6 Librarian Features 6 Benefits of Using Librarian with BarTender 7 File States, Publishing and Workflow in Librarian 8 Don’t Forget About Security! 9 Related Documentation 10 Overview A revision control system is based around the concept of tracking changes that happen within directories or files, and preventing one user from overwriting the work of another. Some revision control systems are also used to establish and track workflow for the progression of a file through a series of states. The collection of files or directories in a revision control system are usually called a repository. These systems allow you to specify a directory, file or group of files that will have their changes tracked. This frequently entails users "checking out" and "checking in" files from a repository. Changes are tracked as the user edits the folder or file; these changes will be visible to all users once the item is checked back in. Each revision is annotated with a timestamp and the person making the change. Some of the benefits of revision control include: l Automatic revision numbering for easy tracking. l Enhanced security. Not only does a "check in" and "check out" system keep one user's work from overwriting another, it can prevent unauthorized or even malicious users from accessing a document. l Some revision control systems include publishing "states," which allow you to track the publishing progress of a document and establish a logical, traceable workflow.
    [Show full text]
  • Use of Information Centric Networks in Revision Control Systems
    Use of Information-Centric Networks in Revision Control Systems January 2011 LARS BROWN ERIK AXELSSON Master’s Thesis at Ericsson Research Supervisors: Börje Ohlman, Ericsson Research and Bengt Ahlgren, SICS Examiner: Mihhail Matskin, KTH TRITA xxx yyyy-nn PREFACE This report is a product of a master thesis work at the School of Information and Communication Technology, KTH. The five months of work and research leading to this final report was conducted at the Swedish Institute of Computer Science (SICS) and Ericsson Research in Kista, Sweden. The authors would like to thank the people who have given us support in our work, without you this thesis would never have been done in time. First of all a special thanks to our supervisors, at SICS, Bengt Ahlgren and at Ericsson Research, Börje Ohlman. Whose support and guidance have been very valuable in keeping the project on the right track. They have helped us in focusing on the essential parts of our problem and have kept us motivated throughout our work. We are also grateful for the advice given by the leader of the OpenNetInf project, Christian Dannewitz, at the University of Paderborn, who gave us design consideration tips in the initial phase of our project work. We have also got help from people at the Palo Alto Research Center (PARC), in particular we would like to thank Paul Rasmussen, Michael Plass and Nick Briggs for their clarifications about the CCNx prototype. Furthermore we would like to thank the coworkers we have been in contact with at SICS and at Ericsson research for their tips and feedback which have helped us during our project.
    [Show full text]
  • TIBCO Designer User's Guide
    TIBCO Designer™ User’s Guide Software Release 5.10 August 2015 Two-Second Advantage® Important Information SOME TIBCO SOFTWARE EMBEDS OR BUNDLES OTHER TIBCO SOFTWARE. USE OF SUCH EMBEDDED OR BUNDLED TIBCO SOFTWARE IS SOLELY TO ENABLE THE FUNCTIONALITY (OR PROVIDE LIMITED ADD-ON FUNCTIONALITY) OF THE LICENSED TIBCO SOFTWARE. THE EMBEDDED OR BUNDLED SOFTWARE IS NOT LICENSED TO BE USED OR ACCESSED BY ANY OTHER TIBCO SOFTWARE OR FOR ANY OTHER PURPOSE. USE OF TIBCO SOFTWARE AND THIS DOCUMENT IS SUBJECT TO THE TERMS AND CONDITIONS OF A LICENSE AGREEMENT FOUND IN EITHER A SEPARATELY EXECUTED SOFTWARE LICENSE AGREEMENT, OR, IF THERE IS NO SUCH SEPARATE AGREEMENT, THE CLICKWRAP END USER LICENSE AGREEMENT WHICH IS DISPLAYED DURING DOWNLOAD OR INSTALLATION OF THE SOFTWARE (AND WHICH IS DUPLICATED IN THE LICENSE FILE) OR IF THERE IS NO SUCH SOFTWARE LICENSE AGREEMENT OR CLICKWRAP END USER LICENSE AGREEMENT, THE LICENSE(S) LOCATED IN THE “LICENSE” FILE(S) OF THE SOFTWARE. USE OF THIS DOCUMENT IS SUBJECT TO THOSE TERMS AND CONDITIONS, AND YOUR USE HEREOF SHALL CONSTITUTE ACCEPTANCE OF AND AN AGREEMENT TO BE BOUND BY THE SAME. This document contains confidential information that is subject to U.S. and international copyright laws and treaties. No part of this document may be reproduced in any form without the written authorization of TIBCO Software Inc. TIBCO, Two-Second Advantage, TIBCO Hawk, TIBCO Rendezvous, TIBCO Runtime Agent, TIBCO ActiveMatrix BusinessWorks, TIBCO Administrator, TIBCO Designer, TIBCO ActiveMatrix Service Gateway, TIBCO BusinessEvents, TIBCO BusinessConnect, and TIBCO BusinessConnect Trading Community Management are either registered trademarks or trademarks of TIBCO Software Inc.
    [Show full text]
  • Evolution of Version Control in Open Source Lessons Learned Along the Path to Distributed Version Control
    Evolution of Version Control in Open Source Lessons learned along the path to distributed version control Chris Aniszczyk (Red Hat) Principal Software Engineer [email protected] http://aniszczyk.org About Me I've been using and hacking open source for ~12 years - contribute{d} to Gentoo Linux, Fedora Linux, Eclipse Eclipse Board of Directors, Committer Representative Member in the Eclipse {Architecture,Planning} Council I like to run! (just finished Chicago marathon in 3:20) Co-author of RCP Book (www.eclipsercp.org) Evolution of Version Control in Open Source | © 2010 by Chris Aniszczyk Agenda History of Version Control (VCS) The Rise of Distributed Version Control (DVCS) Lessons Learned at Eclipse moving to a DVCS Conclusion Q&A Picture 5 Evolution of Version Control in Open Source | © 2010 by Chris Aniszczyk Version Control Version Control Systems manage change “The only constant is change” (Heraclitus) Evolution of Version Control in Open Source | © 2010 by Chris Aniszczyk Why Version Control? VCS became essential to software development because: They allow teams to collaborate They manage change and allow for inspection They track ownership They track evolution of changes They allow for branching They allow for continuous integration Evolution of Version Control in Open Source | © 2010 by Chris Aniszczyk Version Control: The Ancients 1972 – Source Code Control System (SCCS) Born out of Bell Labs, based on interleaved deltas No open source implementations as far as I know 1982 – Revision Control System (RCS) Released as an alternative
    [Show full text]
  • Version Control
    Génie Logiciel Avancé Cours 7 — Version Control Stefano Zacchiroli [email protected] Laboratoire PPS, Université Paris Diderot - Paris 7 5 mai 2011 URL http://upsilon.cc/zack/teaching/1011/gla/ Copyright © 2011 Stefano Zacchiroli License Creative Commons Attribution-ShareAlike 3.0 Unported License http://creativecommons.org/licenses/by-sa/3.0/ Stefano Zacchiroli (Paris 7) Version Control 5 mai 2011 1 / 58 Disclaimer slides in English interactive demos Stefano Zacchiroli (Paris 7) Version Control 5 mai 2011 2 / 58 Sommaire 1 Version control Configuration management diff & patch Version control concepts Brief history of version control systems 2 Revision Control System (RCS) 3 Concurrent Versions System (CVS) 4 Subversion 5 Git 6 References Stefano Zacchiroli (Paris 7) Version Control 5 mai 2011 3 / 58 Sommaire 1 Version control Configuration management diff & patch Version control concepts Brief history of version control systems 2 Revision Control System (RCS) 3 Concurrent Versions System (CVS) 4 Subversion 5 Git 6 References Stefano Zacchiroli (Paris 7) Version Control 5 mai 2011 4 / 58 Sommaire 1 Version control Configuration management diff & patch Version control concepts Brief history of version control systems 2 Revision Control System (RCS) 3 Concurrent Versions System (CVS) 4 Subversion 5 Git 6 References Stefano Zacchiroli (Paris 7) Version Control 5 mai 2011 5 / 58 Change During the life time of a software project, everything changes : bugs are discovered and have to be fixed (code) system requirements change and need to be implemented external dependencies (e.g. new version of hardware and software you depend upon) change competitors might catch up most software systems can be thought of as a set of evolving versions potentially, each of them has to be maintained concurrently with the others Stefano Zacchiroli (Paris 7) Version Control 5 mai 2011 6 / 58 Configuration management Definition (Configuration Management) Configuration Management (CM) is concerned with the policies, processes, and tools for managing changing software systems.
    [Show full text]