If you want to use dynamic tracing in a program you must first issue a call to the mFFH library routine or perform an I/O operation using a standard COBOL statement. This initializes the File Handler.
The library routines provide a means of obtaining the same tracing behavior as setting the FCD flags without the need to have the FCD available. All changes to tracing behavior made using the library routines affect all files subsequently accessed.
To control tracing, issue calls to the MFFH_MODIFY_TRACE library routine. You can:
To disable all the modifications that you have set, issue a call to the library routine MFFH_MODIFY_DISABLE.
For further information see the topics mFFH, MFFH_MODIFY_TRACE and MFFH_MODIFY_DISABLE.