|REN,"NEWNAME.BAS","OLDNAME.BAS"
Renames a file. A file with the new file name may not already exist. Wildcards aren't allowed.
For <text argument>, the USER parameter can also be used (see [[AMSDOS#.7CUSER|||USER]]):
|REN,"0:NEW.BAS","15:OLD.BAS"
the file OLD.BAS from USER 15 will be renamed to NEW.BAS and assigned to USER 0, regardless which USER number was chosen before.