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|  | **SavePreviousBuffer** | **BYTE** |

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The **SavePreviousBuffer **property alerts the FileManager to store a buffer copy on every read action performed by the FileManager. This is useful in any action where the previous contents of a record must be known for comparision.

**Implementation:**

The** **SavePreviousBuffer property is not set by the FileManager, but is a user controlled property.

**See Also:**     [[previousbuffer saved buffer storage .htm|PreviousBuffer]]

**Example:**

**CODE**

**  CASE opCode**

**  OF DriverOp:Add**

**  OROF DriverOp:Append**

**  OROF DriverOp:AddLen**

**  OROF DriverOp:AppendLen**

**   IF ****SELF.SavePreviousBuffer**

**    IF NOT (SELF.PreviousBuffer &= NULL)**

**     DISPOSE(SELF.PreviousBuffer)**

**    END**

**    SELF.PreviousBuffer &= DupString(SELF.Buffer)**

**   END**