in reply to Read Some lines in Tera byte file
- If you need to read line 100 once, read from the beginning.
- If you know you'll need to read line 100 again, remember where (tell) in the file it was located.
And while you're at it, you may as well remember where lines 1 through 99 where located also.
- If you need to read lines at random and often, and quickly: see Re: help reading from large file needed.
It will take a local file, of ( 8*number-of-lines ) bytes, to hold the index, and roughly the same amount of time as wc -l.
With a slightly more sophisticated indexer, the size of the index file can be reduced by half.
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
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In the absence of evidence, opinion is indistinguishable from prejudice.
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