I just found this in the FAQ:
How do I count the number of lines in a file?

One fairly efficient way is to count newlines in the file. The following program uses a feature of tr///, as documented in perlop. If your text file doesn't end with a newline, then it's not really a proper text file, so this may report one fewer line than you expect. 


    $lines = 0;
    open(FILE, $filename) or die "Can't open `$filename': $!";
    while (sysread FILE, $buffer, 4096) {
    $lines += ($buffer =~ tr/\n//);
    }
    close FILE;

[download]

This may well be a stupid question but why might that be preferred to this: 
open(X,filename);
while(<X>;){}
$lines = $.;

[download]

--
“Every bit of code is either naturally related to the problem at hand, or else it's an accidental side effect of the fact that you happened to solve the problem using a digital computer.” M-J D

In reply to How To Count Lines In File? by Cody Pendant

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