The DEFINE and DELETE Functions

When you use the DEFINE and DELETE control statements of AMSERV, you do not need to specify the DSN parameter on the DLBL command:
assgn syscat c
dlbl ijsysct c (perm extent syscat
If the above commands are executed prior to an AMSERV command to define a master catalog, the DEFINE will be successful if you have assigned a data set name using the NAME parameter in the AMSERV file. The same is true when you define clusters or when you use the DELETE function to delete a cluster, space, or catalog.

When you do not specify a data set name, AMSERV obtains the name from the AMSERV file. In the case of defining or deleting space, no data set name is needed. The FILE parameter corresponding to the ddname is all that is necessary, and AMSERV assigns a default data set name to the space.

When you define space on a minidisk using AMSERV, CMS does not check the extents you specify to see whether they are greater than the number of cylinders available. As long as the starting cylinder is a valid cylinder number and the extents you specify are on cylinder boundaries, the DEFINE function completes successfully. However, you receive an error message when you use an AMSERV function that tries to use this space.