TDosStream.Truncate
Truncate the file on the current position.
Declaration
Source position: objects.pp line 351
default
procedure Truncate; Virtual;
Description
If the status of the stream is stOK, then Truncate tries to truncate the stream size to the current file position.
Errors
If an error occurs, the stream's status is set to stError and ErrorInfo is set to the OS error code.
See also
| Name | Description |
|---|---|
| TStream.GetSize | Return the size of the stream. |
| TStream.Truncate | Truncate the stream size on current position. |
Example
Program ex16;
{ Program to demonstrate the TStream.Truncate method }
Uses Objects;
Var L : String;
P : PString;
S : PDosStream; { Only one with Truncate implemented. }
begin
L:='Some constant string';
{ Buffer size of 100 }
S:=New(PDosStream,Init('test.dat',stcreate));
Writeln ('Writing "',L,'" to stream with handle ',S^.Handle);
S^.WriteStr(@L);
S^.WriteStr(@L);
{ Close calls flush first }
S^.Close;
S^.Open (stOpen);
Writeln ('Size of stream is : ',S^.GetSize);
P:=S^.ReadStr;
L:=P^;
DisposeStr(P);
Writeln ('Read "',L,'" from stream with handle ',S^.Handle);
S^.Truncate;
Writeln ('Truncated stream. Size is : ',S^.GetSize);
S^.Close;
Dispose (S,Done);
end.