TOS-Critical Error Handler

The 'Critical Error Handler', called CEH, is the part of the operating system that displays the messages 'Please insert disk B in drive A...' or 'Disk write protected'. Unfortunately this CEH is disabled when a TOS program (ending TOS or TTP) is started. TOS_CEH avoids this problem by installing a new CEH only for TOS programs. The old known messages appear - but not in an alert box but as text, like in MS DOS.