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DC_Nam, Name current application
OS_Poll, poll for an application (OZ usage)
DC_Pol, poll for card usage
OS_Ent, enter an application (OZ usage)
DC_Ent, enter new application (low level OZ usage)
OS_Exit, exit an application (OZ usage)
DC_Bye, exiting current application (OZ usage)
OS_Bye, exit application
OS_Stk, stack current process / application (OZ usage)
OS_Use, process card usage (OZ usage)
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