And this example will create a 50,000 character "line".

$sFile="C:\Temp\wl.txt"

; Construct 10,000 character string.
$sSpace10="          "
For $iIndex=1 To 1000
   $sSpace10000=$sSpace10000+$sSpace10
Next
$nul=Open(1,$sFile,5)
$nul=Writeline(1,$sSpace10000+$sSpace10000+$sSpace10000+$sSpace10000+$sSpace10000)
$nul=Close(1)