I'm working with a really really big file. I'm talking about gigabyte big.

I need to be able to read a line from a particular index as the textfile is consistently being updated. What is the fastest possible solution for achieving this? I am not constrained by space requirement at all.

Edit: More detailed info posted. Suppose I have the following text that needs to be read:

```
Jun 21 09:47:53 ez-x5 user.debug if_comm: [TX] 30 40 05 
Jun 21 09:47:53 ez-x5 user.debug if_comm: [RX] 04 
Jun 21 09:47:53 ez-x5 user.debug if_comm: [TX] 30 40 05 
Jun 21 09:47:54 ez-x5 user.debug if_comm: [RX] 02 30 40 0f 30 32 31 23 64 31 30 32 30 64 64 49 49 49 49 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 64 03 0b 

```

This textfile is consistently updated by our logger. When the text file gets updated, I need to read the new line (separated by \n) of whatever is appended to the log.