If you have a really huge file, your solution needs a lot of memory.
Furthermore you will still need to loop over all the data to re-assemble the broken lines, so your code will not be much simpler.
A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James