You can use the Loader syntax rule restart_spec to satisfy the condition for restarting the export or import.
Syntax
<restart_spec> ::= RESTART <package_guid> <package_guid> ::= <unsigned_integer>
The package_guid is an ID that is created by Loader for each Loader command at runtime. The package_guid is an unsigned integer that is always exactly 24 bytes in length. The package_guid and the computer name of the client of Loader are entered in the table SYSLOADER.TRANSFORMATIONMODEL and logged in the log file. The database user can determine the package_guid of a Loader command from the SYSLOADER.TRANSFORMATIONMODEL table or the log file. You can restart the command by executing this command with the syntax element RESTART <package_guid>.