Management Information Systems In C With Source Code
CSU Channel Islands creates and maintains a number of software applications that provide various services to students, faculty, staff, and the community. Timely access to current source code is necessary both while the software is initially being built and throughout its entire useful lifetime as: defects are discovered and must be corrected; new features and functionality are requested by users; changes are made to hardware or infrastructure; questions arise to as to the exact purpose or result of a piece of software. Proper source code management can also reduce effort and increase the reliability of the development process.
Management Information Systems in c with Source code
A tool can automate a large portion of the SCM process by automatically identifying changes to files and organizing them into revisions and commits. A SCMS provides other benefits to the software development process that would be very costly to do manually, such as providing source code authors with a convenient means to: review revisions to files; review a history of commits to a project; rollback to a particular commit; and work on different features at the same time.
In order for a tool to be useful, developers must make regular use of the tool and decide upon common naming standards such that other developers know where to find the source code they are looking for.
In software engineering, version control (also known as revision control, source control, or source code management) is a class of systems responsible for managing changes to computer programs, documents, large web sites, or other collections of information. Version control is a component of software configuration management.
Changes are usually identified by a number or letter code, termed the "revision number", "revision level", or simply "revision". For example, an initial set of files is "revision 1". When the first change is made, the resulting set is "revision 2", and so on. Each revision is associated with a timestamp and the person making the change. Revisions can be compared, restored, and, with some types of files, merged.
Version control systems are most commonly run as stand-alone applications, but revision control is also embedded in various types of software, such as word processors and spreadsheets, collaborative web docs, and content management systems, e.g., Wikipedia's page history. Revision control enables reverting a document to a previous revision, which is critical for allowing editors to track each other's edits, correct mistakes, and defend against vandalism and spamming in wikis.
In computer software engineering, revision control is any kind of practice that tracks and provides control over changes to source code. Software developers sometimes use revision control software to maintain documentation and configuration files as well as source code.
At the simplest level, developers could simply retain multiple copies of the different versions of the program, and label them appropriately. This simple approach has been used in many large software projects. While this method can work, it is inefficient as many near-identical copies of the program have to be maintained. This requires a lot of self-discipline on the part of developers and often leads to mistakes. Since the code base is the same, it also requires granting read-write-execute permission to a set of developers, and this adds the pressure of someone managing permissions so that the code base is not compromised, which adds more complexity. Consequently, systems to automate some or all of the revision control process have been developed. This ensures that the majority of management of version control steps is hidden behind the scenes.
IBM's OS/360 IEBUPDTE software update tool dates back to 1962, arguably a precursor to version control system tools. A full system designed for source code control was started in 1972, Source Code Control System for the same system (OS/360). Source Code Control System's introduction, having been published on December 4, 1975, historically implied it was the first deliberate revision control system. RCS followed just after, with its networked version Concurrent Versions System. The next generation after Concurrent Versions System was dominated by Subversion, followed by the rise of distributed revision control tools such as Git.
Often the data is thought of as a collection of many individual items, such as files or documents, and changes to individual files are tracked. This accords with intuitions about separate files but causes problems when identity changes, such as during renaming, splitting or merging of files. Accordingly, some systems such as Git, instead consider changes to the data as a whole, which is less intuitive for simple changes but simplifies more complex changes.
When data that is under revision control is modified, after being retrieved by checking out, this is not in general immediately reflected in the revision control system (in the repository), but must instead be checked in or committed. A copy outside revision control is known as a "working copy". As a simple example, when editing a computer file, the data stored in memory by the editing program is the working copy, which is committed by saving. Concretely, one may print out a document, edit it by hand, and only later manually input the changes into a computer and save it. For source code control, the working copy is instead a copy of all files in a particular revision, generally stored locally on the developer's computer;[note 1] in this case saving the file only changes the working copy, and checking into the repository is a separate step.
Revision control systems are often centralized, with a single authoritative data store, the repository, and check-outs and check-ins done with reference to this central repository. Alternatively, in distributed revision control, no single repository is authoritative, and data can be checked out and checked into any repository. When checking into a different repository, this is interpreted as a merge or patch.
Version control is widespread in business and law. Indeed, "contract redline" and "legal blackline" are some of the earliest forms of revision control, and are still employed in business and law with varying degrees of sophistication. The most sophisticated techniques are beginning to be used for the electronic tracking of changes to CAD files (see product data management), supplanting the "manual" electronic implementation of traditional revision control.
Traditional revision control systems use a centralized model where all the revision control functions take place on a shared server. If two developers try to change the same file at the same time, without some method of managing access the developers may end up overwriting each other's work. Centralized revision control systems solve this problem in one of two different "source management models": file locking and version merging.
Merging two files can be a very delicate operation, and usually possible only if the data structure is simple, as in text files. The result of a merge of two image files might not result in an image file at all. The second developer checking in the code will need to take care with the merge, to make sure that the changes are compatible and that the merge operation does not introduce its own logic errors within the files. These problems limit the availability of automatic or semi-automatic merge operations mainly to simple text-based documents, unless a specific merge plugin is available for the file types.
Branching assists with deployment. Branching and merging, the production, packaging, and labeling of source code patches and the easy application of patches to code bases, simplifies the maintenance and concurrent development of the multiple code bases associated with the various stages of the deployment process; development, testing, staging, production, etc.
There can be damage mitigation, accountability, process and design improvement, and other benefits associated with the record keeping provided by version control, the tracking of who did what, when, why, and how. This can allow for better reassessment of why changes were made in order to address problems and solutions going forward. When bugs arise, knowing what was done when helps with damage mitigation and recovery by assisting in the identification of what problems exist, how long they have existed, and determining problem scope and solutions. Previous versions can be installed and tested to verify conclusions reached by examination of code and commit messages.