According to ABBREVIATIONFINDER, MS DOS is an acronym for M icro S oft D isk O perating S ystem, an operating system created by Microsoft, and that most PC computers have installed. DOS is, in addition to an operating system, a set of programs that allow us to manipulate information contained in discs, in this way we can work with ease, comfort and speed with them; In addition, DOS coordinates the operation of the microprocessor so that everything works well inside our computer. Over time Microsoft has been improving DOS, since its first version in 1981. The versions that may exist are used to correct errors detected in the previous version or to improve certain parts of the program; If the variation is in the first figure, it means that important changes have been introduced, the result, for example, of the performance of the new microprocessors, largely to take advantage of their advantages.
History and evolution
Perhaps it is an operating system that is already obsolete and forgotten by most users, but not because it is the basis of the most current OS. Before starting, let’s comment that before the section of history that we are going to explain, there is activity related to the MS-DOS operating system, but that is not of great relevance, such as very little developed versions that did not yet exist under the name of MS-DOS.
The story begins in 1981, with the purchase by Microsoft of an operating system called QDOS, which after making a few modifications, became the first version of the Microsoft operating system MS-DOS 1.0 (MicroSoft Disk Operating System).
From here on, a series of modifications of the operating system take place, up to version 7.1, from which MS-DOS ceases to exist as such and becomes an integrated part of the Windows operating system.
Versions
Among the versions or evolutions of the DOS operating system, there are:
- PC DOS 1.0 – Released in 1981 as a complement to the IBM-PC. First version of DOS. Supports 16 Kb of RAM, 5.25-inch single-sided 160 Kb floppy disks. 22 orders. It allows files with the extension.com and.exe. Incorporates the COMcommand interpreter.
- PC DOS 1.1 – Fixed many bugs, supports double density floppy disks.
- In 1982, version 1.25 appeared, with which support for double-sided floppy disks was added.
- It is not until the following year, 1983, when the system begins to have more functionality, with its version 2.0, which adds support for IBM 10 MB hard drives, and the ability to read-write 5.25 “floppy disks with a capacity of 360Kb..
- In version 2.11 of the same year 1983, new keyboard characters are added.
- In 1984, Microsoft would release its version 3.0 of MS-DOS, and that is when support for 1.2MB high-density disks and the possibility of installing a hard disk with a maximum of 32MB was added.
- In that same year, the support for Microsoft networks would be added in version 3.1.
- It is not until 3 years later, in 1987, when version 3.3 is released with support for the well-known and current 3.5 “floppy disks, and it is allowed to use hard disks larger than 32 MB.
- It is in 1988 when Microsoft released its version 4.0 and with it the support for XMS memory and the possibility of including hard drives of up to 2GB, it should be noted that this version was the biggest catastrophe carried out by the company, since it was full of failures. this was fixed in 1989 with the release of version 4.01 which fixed all these problems and bugs.1
- One of the most relevant advances in the history of MS-DOS, is the transition in 1991 from version 4.01 to version 5.0, in which DOS is already able to load programs in the high memory part of the system using the higher memory (from 640Kb to 1024Kb). In version 5.0, the BASIC programmer and the famous EDIT editor are added. The utilities UNDELETE (Recovery of deleted files), FDISK (Partition management) and a utility to run programs designed for earlier versions of MS-DOS, called SETVER, were also added. It is at the end of 1992 when some problems with UNDELETE and CHKDSK are solved in version 5.0a.
- MS-DOS 6.0 – It appears in with many new features, among them the Doublespace utility that was in charge of compressing the disk and thus having more space available, a basic antivirus (MSAV), a defragmenter (DEFRAG), a memory manager was also included (MEMMAKER) and certain old utilities were suppressed, which by misusing them could destroy data, these utilities were JOIN and RECOVER among others.
- In the same year 1992 version 6.2 comes out, which adds security to the loss of Doublespace data, and adds a new disk scanner, SCANDISK, and solves problems with DISKCOPY and SmartDrive.
- MS-DOS 6.21 – Appeared in the same year 1993, Microsoft suppresses Doublespace and looks for a new alternative for this utility.
- A year later, in 1994, the solution to the Doublespace problem appears, it is the utility of the Stac Electronics company, Drivespace, the one chosen to be included in version 6.22.
- PC DOS 6.3 – Released in April 1994.
- It is already in the year 1995 when Microsoft Windows 95 appears , and that with the appearance of it, it supposes to remove to MS-DOS to a secondary plane.
- However, the MS-DOS system is still in 1995 a new version, 7.0, with which a multitude of utilities are corrected and provides support for long names. The utilities deleted from the previous operating system can be found in the Windows 95 CD directory \ other \ oldmsdos. Add Stacker to replace DoubleSpace.
- MS-DOS 7.1 – In 1997 Windows 95 OSR2 appears, and with it an exhaustive revision of the DOS system, adding support for FAT32partitions, and this is where the history of MS-DOS versions ends. Later integrated into Windows 98 and 98 SE. Supports FAT32 file systems.
- MS-DOS 8.0 – Included in Windows Me. It is the latest version of MS-DOS.
- PC DOS 2000 – Version that solves the problem of the year 2000.
At present, the MS-DOS operating system has little use, for the most part it is only used when Windows is not able to perform the task it is performing or when Windows fails. Many computer technicians use MS-DOS to perform PC maintenance, installations, formatting and partitioning of hard drives, and hard drive scans.
Characteristics
MS-DOS is a single-task, single-user operating system for personal computers.
Commands
Basic commands
Here are some of the commands that MS-DOS used, and that can currently be used from the command line in Windows operating systems. To access the help of these, MS-DOS, from version 6.2 allows the following: command_a_consultar /? (Ex: copy /?). They can be internal (included within COMMAND.COM itself) or external (executable files in the MSDOS directory):
Internal commands
- CD or CHDIR – Change the current directory.
- CD directory_name Changes to the hierarchically lower directory.
- CD \ * PATH – Specifies paths, in which the operating system searches for executable files. It is a command that is usually written in the Config.sys and in batch files.
- CLS – Cleans all the commands and all the information on the screen, except the drive letter used (For example C: \)
- COPY – Copy a file from one directory to another
- COPY CON Make.bat files
- DIR – Lists the directories and files on the current drive or directory.
- FOR – Repeat a command
- PROMPT – Changes the order display line.
- MD – Create a new directory.
- RD or RMDIR – Delete a directory.
- REM – Allows you to insert comments in batch files.
- REN or RENAME – Rename files and directories.
- SET – Assigns values to environment variables.
- TIME – View or change the time of the internal clock.
- TYPE – Shows the content of a file. It is used mainly to view file contents in text format.
- VER – Shows the version of the Operating System.
- VOL – Displays the label of the hard drive and its volume (if it has one).
- MEM – Shows the amount of RAM memory, the amount used and the amount free.
External commands
- ATTRIB – Without parameters, it displays the attributes of the directories and files. With parameters, change the attributes of directories and files.
The attributes of the directories and files are: read (r), write (w), archive (a), hidden (h), system (s). Parameters: signs (plus or minus) and letters r, w, a, and h “v”. Example: Attrib + r *. * (Read-only attribute, for all files in that directory)
- APPEND – Used to specify paths for data files.
- BACKUP – Backs up one or more files from a hard drive to a floppy disk.
- CHKDSK – Checks for hard drive errors. (It can also be used to correct them with the “/ F” parameter)
- DELTREE – Deletes a directory regardless of whether it contains subdirectories with all their contents.
- DISKCOPY – Allows you to make an identical copy from one floppy to another, it belongs to the group of external orders.
- DOSKEY – Allows keeping the orders that have been executed at the indicated point resident in RAM memory.
- FC – Compare files.
- FORMAT – Allows you to create the logical structure in a physical storage unit (hard drives, floppy disks and mass storage units).
- PRINT – Allows you to print files.
These parameters can be used in combination.
- KEYB – Sets the keyboard language according to the added parameter (Example: KEYB SP for the Spanish keyboard).
- LABEL – Displays or changes the label of the hard drive.
- MEM – Shows RAM, occupied space and free space.
- MOVE – Move or reposition a directory and / or files. Also rename subdirectories.
- SUBST – Creates a virtual logical drive from a directory.
- TREE – shows the directories as a tree
Redirects
- < – Re-addressing of standard input. Its syntax is command <file.
- > – Re-addressing of standard output. Its syntax is command> file. If the file does not exist, it creates it. If it already existed, it overwrites its content.
- >> – Redirection of standard output to an existing file. Its syntax is command >> file. If the file does not exist, it creates it. If it already exists, add the command output after the previous content of the file.
