Pointers

See https://www.freepascal.org/docs-html/ref/refse15.html

null pointers in pascal is nil.

See also https://en.wikibooks.org/wiki/Pascal_Programming/Pointers

var
  p: ^integer;
  i: integer;
begin
  i := 3;
  p := @i; // get the address of i
  p^ += 2; // equivalent to *p += 2 in c/c++
  Writeln('i is ', i); // is is 5
end.

• The new function from https://www.freepascal.org/docs-html/3.2.0/rtl/system/new.html

  It is declared as:

  procedure New(
    var P: Pointer
  );
  

  Note that the argument type is Pointer, which is an untyped pointer. Also note the argument is var, meaning it is an input/output argument

  Example:

  var
   p: ^integer;
  begin
    New(p); // allocate space and save the address to p
    p^ := 10;
    writeln ('p^ is ', p^); // p^ is 10
    Dispose(p); // free p
  end.
  

• GetMem() and FreeMem()

  See https://www.freepascal.org/docs-html/3.2.0/rtl/system/freemem.html

• FillByte(), FillChar(), FillWord(), FillDWord(), are similar to memset in C/C++.

  https://www.freepascal.org/docs-html/3.2.0/rtl/system/fillchar.html