DIGITAL RESEARCH(r) CP/M Plus TM (CP/M Version 3) Operating ...

The USER Command CP/M 3 User's Guide
The USER Command
Syntax: USER {number}
Explanation: The USER command sets the current user number. When you start
CP/M 3, 0 is the current user number. You can use a USER command
to change the current user number to another in the range 0-15.
CP/M 3 identifies every file with a user number. In general, you can
access only files identified with the current user number. However, if
you mark a file in user 0 with the SYS attribute, the file can be accessed
from all other user numbers.
Examples: A > USER
The system command prompts for the user number, as follows:
Enter User# : 5
5A>
The current user number is now 5 on drive A.
A>USER 3
3A>
This command changes the current user number to 3.
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