The new HONOR_DSNTYPE_PDSE parameter in PARMLIB member IGDSMSxx provides an option to allow you to ensure that a partitioned data set is created. If HONOR_DSNTYPE_PDSE=YES, then creating a data set using a value for DSNTYPE of LIBRARY or HFS (both of which indicate that a PDSE should be created) results in a partitioned data set being created, regardless of the values for data set organization or directory blocks. If HONOR_DSNTYPE_PDSE=NO (the default), then data set creation is not changed, and the value for DSNTYPE may be ignored, depending on the values for the other attributes.
You can also set the value for HONOR_DSNTYPE_PDSE with the SETSMS command.
For details on IGDSMSxx, refer to the topic about IGDSMSxx in z/OS MVS Initialization and Tuning Guide.
For details on the SETSMS command, refer to the topic about SETSMS in z/OS MVS System Commands.