Move the pointer in a binary file to a new record position System unit
 procedure Seek(var FileHandle File; RecordNumber LongInt);
The Seek procedure moves the current record position in an open binary file given by FileHandle to a new position RecordNumber.
The file must have been assigned with AssignFile and opened with Reset or ReWrite.
For untyped files, the record size is set with the Reset or ReWrite routine used.
For typed files, the record size is SizeOf the file type.
The first record in a file is record 0.
Use SeekEoln or SeekEof to move the file pointer on a text file.
Related commands
EofReturns true if a file opened with Reset is at the end
EolnReturns true if the current text file is pointing at a line end
FileDefines a typed or untyped file
FilePosGives the file position in a binary or text file
SeekEolnSkip to the end of the current line or file
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Example code : Repositioning in a Word type file
  myWord, myWord1, myWord2, myWord3, myWord4 : Word;
  myFile : File of Word;

  // Try to open the Test.cus binary file in write only mode
  AssignFile(myFile, 'Test.cus');

  // Write a few lines of Word data to the file
  myWord1 := 12;
  myWord2 := 34;
  myWord3 := 56;
  myWord4 := 78;
  Write(myFile, myWord1, myWord2, myWord3, myWord4);

  // Close the file

  // Reopen the file for read only purposes
  FileMode := fmOpenRead;

  // Seek (move) to the start of the 3rd record
  Seek(myFile, 2);    // Records start from 0

  // Show this record
  Read(myFile, myWord);
  ShowMessage('Record 3 = '+IntToStr(myWord));

  // Close the file
Show full unit code
  Record 3 = 56
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