Everytime you power up or reset your computer, CP/M 3 looks for a
  special SUBmit file named PROFILE.SUB to execute.  If it does not
  exist, CP/M 3 resumes normal operation.  If the PROFILE.SUB  file
  exists,  the system executes the commands in the file.  This file
  is convenient to use if you regularly execute a set  of  commands
  before you do your regular session on the computer.