Data sets used by the API

The following table lists the data sets that the API uses. In general, you do not have to allocate or free these data sets. Instead, invoke the RCCUALOC API to create the data sets, allocate the associated DD names, and free the data sets as described in TSO Client API Functions. If a required data set already exists, it is reused; otherwise, one must be created by using the RCCUALOC API function.
Note: The LRECL and BLKSIZE for username.TSC.CMD have changed from these attributes for the data set allocated prior to this release of z/OS® Extensions. The username is now your TSO logon ID.

If the username.TSC.CMD data set already exists with different attributes (namely, a smaller LRECL and BLKSIZE), and if the data set is not deleted first, unexpected I/O errors might occur.

If you already have these data sets allocated with different data set attributes, in general, it is best to delete them before invoking the API and to run the RCCUALOC API function to allocate the data sets with the appropriate data set attributes.

To keep the existing members in the username.TSC.CMD PDS, follow this procedure:

  1. Rename the PDS, for example, to username.TSC.CMDOLD.
  2. Allocate username.TSC.CMD with the attributes shown in Results of data sets used by the API.
  3. Copy the existing members from the old PDS to the newly allocated one.
  4. Delete the old (renamed) PDS.
Table 1. Results of data sets used by the API
DATA SET NAME RECFM DSORG LRECL BLKSIZE MEMBER NAME
username.TSC.CMD VB PO 14328 14336
  • APIIN
  • APICCCMD
  • APIOUT
  • APIERR
username.TSC.JCL FB PO 80 3120 APIMAP
username.TSC.TAPILOG VB PS 255 6160
username.TSC.TAPILOG2 VB PS 255 6160

For a list of DD names associated with these files, see RCCUALOC.