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Presents historical artifacts from the history of:

Rational R1000/400 Tapes

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artifacts from Datamuseum.dk's BitArchive.

See our Wiki for more about Rational R1000/400 Tapes

Excavated with: AutoArchaeologist - Free & Open Source Software.


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Index: ┃ B T

⟦4ed11fec9⟧ TextFile

    Length: 1723 (0x6bb)
    Types: TextFile
    Names: »B«

Derivation

└─⟦149519bd4⟧ Bits:30000546 8mm tape, Rational 1000, !projects 93-07-13
    └─ ⟦124ff5788⟧ »DATA« 
        └─⟦this⟧ 
└─⟦a7d1ea751⟧ Bits:30000550 8mm tape, Rational 1000, !users!projects 94_04_11
    └─ ⟦129cab021⟧ »DATA« 
        └─⟦this⟧ 
└─⟦f64eaa120⟧ Bits:30000752 8mm tape, Rational 1000, !projects 93 02 16
    └─ ⟦6f12a12be⟧ »DATA« 
        └─⟦this⟧ 
└─⟦2f6cfab89⟧ Bits:30000547 8mm tape, Rational 1000, !projects 94-01-04
    └─ ⟦d65440be7⟧ »DATA« 
        └─⟦this⟧ 

TextFile

package body Fifo is

    Tab : array (1 .. Size) of Element;
    Head, Tail : Positive := 1;


    task body Task_Fifo is

    begin  
        loop
            select
                accept Get (Item : out Element; Result : out Boolean) do  
                    if not Is_Empty then
                        Get (Item);
                        Result := True;  
                    else
                        Result := False;
                    end if;
                end Get;
            or
                accept Put (Item : in Element; Result : out Boolean) do
                    if not Is_Full then
                        Put (Item);
                        Result := True;
                    else
                        Result := False;
                    end if;
                end Put;
            or
                accept Clear do
                    Clear;
                end Clear;
            or

                terminate;
            end select;
        end loop;
    end Task_Fifo;



    procedure Clear is
    begin
        Head := 1;
        Tail := 1;
    end Clear;


    function Is_Empty return Boolean is
    begin
        return Head = Tail;
    end Is_Empty;


    function Is_Full return Boolean is
    begin
        return Tail + 1 mod Size = Head;
    end Is_Full;


    procedure Get (Item : out Element) is
    begin
        Item := Tab (Head);
        if Head = Size then
            Head := 1;
        else
            Head := Head + 1;
        end if;
    end Get;


    procedure Put (Item : in Element) is
    begin
        Tab (Tail) := Item;
        if Tail = Size then
            Tail := 1;
        else
            Tail := Tail + 1;
        end if;
    end Put;

end Fifo;