DOS (Disk Operating System) commands are instructions that can be executed to interact with certain functions of the machine. In the early versions of MS-DOS, it was necessary to know this language in order to use the operating system. The interface was simplified in 1984 when Microsoft introduced Windows, and, while initially it simply replaced the MS-DOS interface with DOS commands operating under the hood, these commands later became obsolete for the functioning of the system. However, they are still executable from the command line, by running a batch file or even by running certain applications.

 

What is a command line? What is a batch file?

 

The command prompt (sometimes called the command line or command processor) is located at C:\WINDOWS\system32\cmd.exe, which can be opened more quickly by going to Start > All programs > Accessories > Command Prompt, or even more quickly by going to Start > Run and typing CMD. DOS commands can be executed through this environment.

A batch file is a file (which can be created with Notepad), whose commands written inside will be executed when the file is run through the command prompt. The extension of this type of file is .bat.

 

DOS commands are mostly applications (in .exe format), and can therefore be executed by other application external to cmd.exe. Some (including IF, DEL o ERASE, GOTO etc...) are interpreted directly by the prompt. Such commands are called internal commands, and generally cannot be executed in an environment other than the command prompt.

 

Wildcards

 

Wildcards are characters that replace one or a group of characters, usually alphanumeric (a-z, A-Z, 0-9).

 

*    It is generally used for file names or extensions that you do not know, or, more

      frequently, to indicate a group of files or directories with the same name,

      extension or to indicate all files in a directory.

      Example: Delete all files with the .txt extension inside the C:\dump directory:

      del "C:\dump\*.txt"

 

Other special characters:

 

@    hides a command (i.e. does not display it in the command prompt).

        Example: Hide the command SHUTDOWN /S /T 100 /C "Hello!":

        @shutdown /s /t 100 /c "Hello!" 

        This special character can be omitted if ECHO is disabled. See ECHO.

 

&    joins two commands on the same line.

       Example: join the command "C:\d.txt" and the command ECHO The file d.txt has been

       opened correctly:

       "C:\d.txt" & echo The file d.txt has been opened correctly

 

Syntax warnings: Options in square brackets [ ] can be omitted. If two or more options are inside a square bracket, this means that if one is omitted, the othe must also be omitted. If the symbol | is inside a square bracket, it means that you can choose between two options (or more), but you cannot choose both. Commands inside curly braces { } that contain the | symbol, mean that at least one option must be chosen and not more than one of those specified. Words in all-capital letters mean that they cannot be replaced (but can be omitted if inside square brackets [ ]), while words in lowercase indicate that they must be replaced by a numeric or string value. Double quotes must be " " and not “ ”. The same applies to single quotes: ' ', not ‘ ’. The slash / can often be replaced by the hypen -. If the syntax is not respected, errors will be encountered, and consequently the execution of the program will be interrupted. The ellipsis ... indicates that repetition of the previous parameter is allowed (specifying, of course, additional information).

ASSOC          Display or change the applications associated with the file extensions.

AT                   Schedule the execution of commands or programs on a computer.

ATTRIB          Display or change the attributes of a file.

BREAK          Toggle extended control of CTRL + C (^C).

CACLS           Display or modify file access control lists (ACL).

CALL              Call one batch program from another.

CD                   Display the name or change the current directory.

CHCP             Display or set the active code page number.

CHDIR            Display the name or change the current directory.

CHKDSK       Check a disk and display a status report.

CHKNTFS      Display or modify the verification of a disk during boot.

CLS                 Clear the screen.

CMD                Start a new instance of the Windows command interpreter.

COLOR           Set the default foreground and background colors of the console.

COMP             Compare the contents of two files or a group of files.

COMPACT     Display or change file compression on NTFS partitions.

CONVERT     Convert FAT volumes to NTFS. The current drive cannot be converted.

COPY              Copy one or more files to another location.

DATE              Display or set the date.

DEL                 Delete one or more files.

DIR                  Display a list of files and subdirectories in a directory.

DISKCOMP   Compare the contents of two floppy disks.

DISKCOPY    Copy the contents of one floppy disk to another.

DOSKEY        Edit command lines, recall Windows commands, create macros.

ECHO              Display messages or turn command echo on and off.

ENDLOCAL   End localization of environment changes in a batch file.

ERASE           Delete one or more files.

EXIT                 Terminate the CMD.EXE program (the command prompt).

FC                    Compare two files or group of files and display the differences between them.

FIND                Searches for a text string in a file or files.

FINDSTR        Search for strings in files.

FOR                 Execute a specified command for each file in a group of files.

FORMAT        Format a disk for use with Windows.

FTYPE            Display or change the file types used in extnesion associations of files.

GOTO             Direct the Windows command interpreter to a labeled line in a batch program.

GRAFTABL  Enable Windows to display an extended character set in graphic mode.

HELP             Provide help information for Windows commands.

IF                     Perform conditional processing in a batch program.

LABEL           Create, change or delete the volume label of a disk.

MD                  Create a directory.

MKDIR           Create a directory.

MODE            Configure a system device.

MORE            Display output one screen at a time.

MOVE            Move one or more files from one directory to another.

PATH             Display or set a search path for executable files.

PAUSE          Suspend processing of a batch file and display a message.

POPD             Restore the current directory to its previous value saved with PUSHD.

PRINT            Print a text file.

PROMPT       Change the Windows command prompt.

PUSHD          Save the current directory and then change it.

RD                  Remove a directory.

RECOVER    Recover readable information from a damaged of defective disk.

REM               Log comments (notes) to batch or CONFIG.SYS files.

REN               Rename files.

RENAME      Rename files.

REPLACE    Replace files.

RMDIR          Remove a directory.

SET                Display, set, or delete Windows environment variables.

SETLOCAL  Begin localization of environment changes in a batch file.

SHIFT            Change the position of replaceable parameters in batch files.

SORT            Sort the input.

START          Launch a separate window to run a program or specified command.

SUBST          Associate a path with a drive letter.

TIME              Display or set the system time.

TITLE            Set the window title for a CMD.EXE session.

TREE            Graphically display the directory structure of a drive or path.

TYPE            Display the contents of a text file.

VER              Display the Windows version.

VERIFY        Tell Windows whether or not to verify if files were written correctly

                       on a disk.

VOL              Display a volume label and the disk serial number.

XCOPY        Copy files and directory structures.