GLO1460E Directory increase requires exclusive control, but was unable to obtain it; r15=`rc`.

Explanation
 During the dynamic PDS directory increase function, Advanced Allocation Management  required
exclusive control of the data set to maintain the integrity of the
PDS directory, but an attempt to obtain it failed. Recovery cannot
continue. 

User response
 Note the return code rc and contact IBM® Software Support with
the diagnostic information. 