Allocation errors

ISPF attempts to recognize inconsistent attributes for partitioned and sequential data sets before allocating them. However, when conditions outside ISPF's control result in the allocation of such a data set, the Allocation Error panel (Figure 1) is displayed. These conditions are caused by:

A data class that specifies inconsistent attributes
Attributes entered on the Allocate New Data Set panel that create inconsistency by overriding other attributes specified by the data class.

Figure 1. Allocation Error Panel (ISRUADCS)

This screen dump is titled "Allocation Error", and tells you want to do if the specified data set has zero block size.

The term inconsistent attributes refers to incompatible values that have been specified for one or more of these items: Space units; Primary or Secondary quantity; Directory blocks; Record format; Record length; Block size.

For example, if you allocate a data set with an undefined record format (RECFM=U) and a block size of zero (BLOCKSIZE=0), some ISPF functions (such as Move and Copy) and services (such as LMMOVE, LMCOPY, and LMINIT) cannot use the data set.

However, when either the linkage editor or the IEBCOPY utility has been called, these functions and services determine the best block size for the data set. Then, when the data set has a block size greater than zero, the ISPF functions and services listed can be used.

The Allocation Error panel gives you the opportunity to delete such a data set because other ISPF functions, such as View (option 1) and Edit (option 2), may not be able to use it.

For information about allocation errors and how they affect data set promotion when using SCLM, refer to z/OS ISPF Software Configuration and Library Manager Guide and Reference.