The description below is from the book
DOS the Easy Way by Everett Murdock Ph.D. CLICK HERE for information about downloading the book.

Type: External (2.0 and later)


ASSIGN x=y [...] /sta

Purpose: Redirects disk drive requests to a different drive. (In DOS Version 6, this program is stored on the DOS supplemental disk.)


Use the ASSIGN command to change drive assignments from the drive indicated by the first letter you enter (x), to the drive indicated by the second letter (y) entered. Do not enter a colon after the drive letters.

Entering the command without any parameters causes all drive reassignments to be reset to normal. The equal sign is optional.

In DOS Version 5 you can use the /sta (status) parameter to display a report of the currently assigned drives.

This command is especially useful when you are using a program that automatically attempts to read or write to a specified drive. By reassigning that drive letter, you tell DOS to ignore requests to the first drive letter and instead carry out both reads and writes on the second drive letter. When you want DOS to again carry out drive requests as usual, enter ASSIGN without any options.

You can use this command with application programs that attempt to act on drives you don`t want to use (or don`t have installed in your computer).

This command should not be used with other DOS commands that need to get drive information. The FORMAT, DISKCOPY and DISKCOMP will ignore any drive reassignments. Also, don`t use the BACKUP, RESTORE, LABEL, JOIN, SUBST, or PRINT COMMANDS with redirected drives.


assign a=b

DOS sends any requests for drive A to drive B. After this form of the command is entered, the command

dir a:

will result in a display of the files on drive B instead of drive A.

You can reassign more than one drive at a time (leave a space between entries). For example, enter

assign a=b c=b

Requests for either drive A or drive C would automatically be sent to drive B.

For example, if you enter

dir a:

DOS will display a directory of the files on drive B (not of drive A).


assign /sta

and a report of the assigned drives will be displayed in the following format:

Original A: set to D:
Original B: set to D:

For more information about this command, refer to the downloadable book DOS the Easy Way.

Copyright 1985 - 2014 by Everett Murdock

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