I've tried $Library_Index{<$Library>} = tell(ARGV), scalar <$Library> until eof();but it takes very long time to do.

How long?

I wonder if there is a better way to do it since this would be a bottleneck.

If you are re-using the file many times you could construct the index and write it to a separate file. It should be substantially quicker to read the index from a file than to construct it from scratch each time.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
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In reply to Re^3: Reading HUGE file multiple times by BrowserUk
in thread Reading HUGE file multiple times by Anonymous Monk

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