The CRITICAL command, along with its qualifiers, displays and/or modifies the status and contents of the critical section for the current region. The critical section provides a control mechanism. This field identifies, by its process identification number (PID), the process presently managing updates to database.

The format of the CRITICAL command is:

         CR[ITICAL] -I[NIT]
                    -O[WNER]
                    -REL[EASE]
                    -REM[OVE]
                    -S[EIZE]
        

By default, the CRITICAL command assumes the -OWNER qualifier, which displays the status of the critical section.