This should specify the A-Shell base directory (i.e. the directory where miame.ini is found, and under which are various control directories such as doc, bin, dsk0, etc. Under UNIX, this variable is usually predefined in a common login profile (such as /etc/profile or $HOME/bash_profile), so that the miame.ini specification does not have to be explicitly added to the A-Shell command line. Under Windows, the miame.ini specification is usually included in the command line associated with the shortcut/icon, eliminating the motivation for pre-defining it. Note that although A-Shell does not automatically define this variable, it will recognize and interpret %MIAME% as the directory where the current miame.ini is located.