Description

The IXCSETUS macro updates the user state field that the cross-system coupling facility (XCF) maintains for an XCF member. The target member must be in the same XCF group as the caller and must be in one of the following states: created, active, quiesced, or failed; the caller can be the target member. The caller specifies, on the NEWUS parameter, what the new value of the target member's user state field is to be. When a change is made to the user state field, XCF broadcasts the change to those active members in the group that have group user routines.

Before it requests a change in the user state field, a caller can ask XCF to confirm the current value of the field. XCF compares the current value with a compare value that COMPUS identifies. This operation is similar to a compare and swap instruction.

If the current value and the compare value match, XCF replaces the current value with the value that NEWUS points to.
If the current value and the compare value do not match, XCF leaves the current value of the user state field as it is. If you specify OLDUS, XCF copies the current value to that field. The USLEN parameter determines the length of the data XCF copies to OLDUS.

If the OLDUS and COMPUS parameters both point to the same field, XCF replaces the compare value with the current value.