Delphi in a Nutshell

Name

Seek Procedure

Syntax

procedure Seek(var F: File; RecordNumber: LongInt);

Description

The Seek procedure moves the file position to RecordNumber. Seek is not a real function.

Tips and Tricks

• You cannot call Seek for a TextFile. If you must seek to a specific position, use the Windows API:

// Seek to a byte position in a text file. See SetInOutRes for the
// same procedure with error-handling. Assume the buffer is empty.
procedure TextSeek(var F: TextFile; Pos: LongInt);
begin
  SetFilePointer(TTextRec(F).Handle, Pos, nil, File_Begin);
end;

• The start of the file is record number 0.

• If F is an untyped File, the record size is set when you open the file with Reset or Rewrite.

Example

// Rewind a file to the beginning.
Seek(F, 0);

// Jump to the end of a file.
Seek(F, FileSize(F));

See Also

File Keyword, FilePos Function, IOResult Function