gtpd1m0fDatabase Reference

General Data Set Addresses

A TPF general data set is directly related to the meaning of an MVS data set. The records of a data set are allocated sequentially in the same module (or MVS volume). A special macro, file data chain transfer (FDCTC), permits you to process records that are not restricted to the standard TPF file record sizes. A file with standard record sizes is processed online by using the TPF standard find and file type macros.

File referencing for general data sets is slightly different from the procedures used to access fixed record types and pool records. Two general data set macros are provided to allow ECB-controlled programs to access records in a general data set:

 GDSNC 
Associates a data set name with a unique entry.

 GDSRC 
Calculates the file address of a specific record in the data set named by the GDSNC macro.

These macros set up a user-specified data level that is appropriate for accessing records in a general data set for the find and file type macros using a physically oriented interface that is transparent to the user.