On Alpha and Integrity server systems, allows an OpenVMS thread
    to assume the identity of another persona.

    Format

      SYS$PERSONA_ASSUME  persona ,[flags], [previous], [acmode]

    C Prototype

      int sys$persona_assume  (unsigned int *persona, unsigned int

                              flags, unsigned int *previous, unsigned

                              int acmode);

  Additional Information (explode) :

• Arguments