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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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OS_Fn, handle functions (OZ usage, extended API in OZ 4.6 and newer)
OS_Gth, get tri-handle (OZ usage)
OS_Vth, verify tri-handle (OZ usage)
OS_Fth, free tri-handle (OZ usage)
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OS_Sp, set Panel and PrinterEd values
OS_Nq, read Panel and PrinterEd values (extended API in OZ 4.5 and newer)
Time
GN_Gmt, fetch machine time
GN_Gtm, convert an ASCII string to a time in internal format
GN_Msc, miscellaneous time operations
GN_Pmt, put (set) machine time
GN_Ptm, write internal time as ASCII string
GN_Sdo, send date and time to standard output
OS_Dly, delay a given period
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