SVC 031
SVC 031 is a Type 4 SVC issued by the Force End of Volume (FEOV) macro. It is similar to the EOV macro, called by SVC 055.
The FEOV macro gets a LOCAL lock and calls load module IGC0003A.
The FEOV is used by programs that process physical datasets. It gets the next volume mounted, verified, and ready for processing.
Reference Sources
IBM z/OS MVS Diagnosis Reference
IBM z/OS DFSMS Using Data Sets
IBM z/OS DFSMS Macro Instructions for Data Sets