Flushes buffered text file data to the file System unit
 procedure Flush ( var FileHandle : TextFile ) ;
The Flush procedure flushes unwritten text file data to disk.
The same effect can be achieved by closing the file. In fact, this is more likely to be effective, since Flush simply passes the flush request to the Operating System, which may in turn be doing its own buffering, and possibly caching.
Related commands
AssignFile Assigns a file handle to a binary or text file
CloseFile Closes an open file
File Defines a typed or untyped file
TextFile Declares a file type for storing lines of text
Example code : Flushing after writing lines to a file
  myFile : TextFile;
  text   : string;

  // Try to open the Test.txt file for writing to
  AssignFile(myFile, 'Test.txt');

  // Write a couple of well known words to this file
  WriteLn(myFile, 'Hello');
  WriteLn(myFile, 'World');

  // Close the file

  // Reopen the file for reading

  // Display the file contents
  while not Eof(myFile) do
    ReadLn(myFile, text);

  // Close the file for the last time
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