Simple WHOHAS routine
When another user has locked the file that you want to use, a simple way to identify that user is via a “WhoHas” program.
Every shop uses the same basic routine, which invokes the GQSCAN macro. The GQSCAN requests a scan of the GRS (Global Resource Serialization) queues to locate which user(s) already have a specific file (resource) allocated to them by the operating system.
