Just jump to a very random position via seek() and then read the next line you find:

open my $fh,'<',$some_file or die $!;
my $size = -s $fh;
seek $fh, rand($size) , 0;
<$fh>; #throw away current line;

my $randomline = <$fh>;

close $fh;

[download]

Only problem is that you might seek() to a position in the last line of the file and will get no random line. But it's not too hard to solve this problem.

--
http://fruiture.de

In reply to Re: reading a random line from a file by fruiture
in thread reading a random line from a file by Anonymous Monk

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