So I have a text file of arbitrary length, and each line contains a discrete piece of data. I would like to read a random line from this file into $_. One way, of course, would be as follows: 
@lines = <file>;  #read the whole friggin' thing into memory
$_ = @lines[int rand scalar @lines - 1];

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But that can be prohibitively expensive for large text files. What's the best way to do this? Thanks.

In reply to reading a random line from a file by Anonymous Monk

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