The description below is from the book DOS the
Easy Way by Everett Murdock Ph.D.
for information about downloading the book.
ASSIGN 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
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.
DOS sends any requests for drive A to drive B. After this form of the
command is entered, the command
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
For example, if you enter
DOS will display a directory of the files on drive B (not of drive
and a report of the assigned drives will be displayed in the following