Implementation strategy FLEXPART namelist input 1. use pathnames file if provided as 1st argument - if argument exists, try to open as text file - if it can be opened, proceed as before - if an error occurs, give a good error message - if no argument is given, look for the classic pathnames file in the current directory 2. namelist input for COMMAND - use switches named as current parameters - try to open as namelist file - on format error, try to open as old file - fail on further errors as bad format 3. namelist input for RELEASES - use switches named as current parameters - try to open as namelist file - on format error, try to open as old file - fail on further errors as bad format