Microsoft DOS backup command

backup commandAbout backup
Availability
Backup syntax
Backup examples

About backup

MS-DOS application that enables users to backup their data on their computer.

Availability

The backup command is an external command available in the below Microsoft operating systems. With MS-DOS 4.0x and earlier the backup.com external file was used. In the last version of MS-DOS (version 5) to support the backup command it used backup.exe as the external file.

MS-DOS 2.x to MS-DOS 5.00a

Note: MS-DOS 6.0, 6.2, 6.21, and 6.22 users use the msbackup command. However, this file is still available to these users on the MS-DOS 6.0 and 6.22 supplemental disk.

Backup syntax

MS-DOS 2.x - 5.x syntax

BACKUP [Source:\Path\Filename] [Target:] [/s] [/m] [/a] [/d:date] [/t:time] [/f:size] [/L:LogDrive:\Path\Log]

Source:\Path\Filename The source, path, and filename of the location of the file that you want to backup.
Target: The target drive for the backup file.
/s Makes a backup of all files, directories, and subdirectories in the specified source location.
/m Backup all files that have changed since the last backup.
/a Adds a new backup file to existing backups instead of overwriting them.
/d:date Backup files that have been created or modified since the date specified.
/t:time Backup files that have been created or modified after this time.
/f:size Create backup files in a specific size so they can be saved to an external storage such as a floppy disk drive.
/L:LogDrive:\Path\Log Create a log of the backup and specify the location of where the log is to be saved.

Backup examples

backup c:\work\*.* d: /s

The above example would create a backup of all the files and subdirectories in the work directory and save the backup to the d: drive.

Additional information

  • See our backup definition for further information and related links on this term.