SD.H seek() is not working

Hello every body
There is a bug in file seek() . this function is change the position in the opened file as required but when trying to write in a specific location it always append the data at the end of the file no matter what the seek value was.
the solution is :
to use
File dataFile = SD.open("datalog.txt", O_READ| O_WRITE | O_CREAT);
instead of
File dataFile = SD.open("datalog.txt", FILE_WRITE);

this has been discussed recently in the forum on similar topic; search for it to see if it's the same issue - it's still on the first page of the forum

(here is the link if you are too tired...)