The debugger built-in symbols provide options for specifying
    program entities and values in debugger commands, as follows:

    Function       Symbols

    Specify        %Rn, %R31, %AP, %FP, %SP, %PC, %PSL, %Vn, %VCR,
    Alpha          %VLR, %VMR, %Fn, %F31
    and VAX
    registers

    Specify        %ARn, %Bn, %CRn, %Fn, %IPn, %IR0, %PRED, %Pn, %Rn,
    Itanium[R]     %SR
    registers

    %LANGUAGE      Specify the current language

    %NAME          Construct identifiers

    %PARCNT        Count parameters passed in command procedures

    %BIN, %DEC,    Control radix
    %HEX, %OCT

    %CURLOC,       Specify consecutive program locations and the
    %NEXTLOC,      current value of an entity
    %PREVLOC,
    %CURVAL

    %LABEL,        Specify numeric labels and line numbers
    %LINE

    %ADDR,         Specify the argument passing mechanism for the
    %DESCR,        CALL command
    %REF, %VAL

    Specify        %ADAEXC_NAME, %EXC_FACILITY, %EXC_NAME, %EXC_
    processes,     NUM, %EXC_SEVERITY, %PROCESS_NAME, %PROCESS_PID,
    tasks, or      %PROCESS_NUMBER, %NEXT_PROCESS, %PREVIOUS_PROCESS,
    information    %VISIBLE_PROCESS, %ACTIVE_TASK, %CALLER_TASK,
    about          %NEXT_TASK, %TASK. %VISIBLE_TASK
    exceptions

    Specify        %PAGE, %WIDTH, %DECWINDOWS, %CURDISP, %CURSCROLL,
    information    %NEXTDISP, %NEXTINST, %NEXTOUTPUT, %NEXTSCROLL,
    about the      %NEXTSOURCE, %SOURCE_SCOPE, %INST_SCOPE, %CURRENT_
    interface      SCOPE_ENTRY, %NEXT_SCOPE_ENTRY, %PREVIOUS_SCOPE_
                   ENTRY