Using the DSNAME and DISP file resource definition parameters

You can define a data set to CICS by specifying the DSNAME and DISP parameters when you define the file.

You can specify these parameters either using RDO for files, or by using DFHFCT macros (BDAM files only). If you want to use DSNAME and DISP from the file definition, do not provide a DD statement for the data set in the startup job stream, because the attributes in the DD statement will override those in the CICS resource definition.

If you use DSNAME and DISP on the file definition, CICS allocates the data set dynamically at the time the first file referencing that data set is opened; that is, immediately before the file is opened. At this stage, CICS associates the file name with the data set.

When CICS applications subsequently refer to the data set, they do so by specifying the file name. When you define a data set in this way, it is automatically deallocated by CICS when the file is closed.

For information about using the DSNAME and DISP parameters, see SRT- system recovery table and FCT- file control table