[Flex-help] yyrestart's yyin vs. input_file

[Chris v. <che...@gm...>]

Hello,

I have a very silly developer-level question.  I see the following
generated yyrestart function (reformatted for consistency):

void yyrestart ( FILE * input_file )
{
  if ( ! YY_CURRENT_BUFFER )
  {
    yyensure_buffer_stack ();
    YY_CURRENT_BUFFER_LVALUE =
      yy_create_buffer( yyin, YY_BUF_SIZE );
  }
  yy_init_buffer( YY_CURRENT_BUFFER, input_file );
  yy_load_buffer_state( );
}

Why is yy_create_buffer called with yyin but yy_init_buffer called with
input_file?

I don't know that this is incorrect (or otherwise causing any problems), I
just noticed it and it seemed strange.  I'm using Flex 2.6.4.

-Chris