FAQ 5.3 How do I count the number of lines in a file?

FAQ 5.3 How do I count the number of lines in a file?

am 11.10.2007 15:03:03 von PerlFAQ Server

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5.3: 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;

This assumes no funny games with newline translations.



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