/**/
parse arg size in out
if size == '' | in == '' | out == '' then do
  say 'Usage: mkbigfile.cmd <size> <in_file> <out_file>'
  exit
end
len = 512
data = charin(in, 1, len)
if length(data) < len then len = length(data)
'@del' out '1>nul 2>nul'
do i = 1 to size % len
  call charout out, data
end
call charout out, left(data, size // len)
call charout out