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

[PerlFAQ Server]

This is an excerpt from the latest version perlfaq5.pod, which
comes with the standard Perl distribution. These postings aim to
reduce the number of repeated questions as well as allow the community
to review and update the answers. The latest version of the complete
perlfaq is at http://faq.perl.org .

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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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[C.DeRykus]

On Dec 16, 3:00 am, PerlFAQ Server <br...@theperlreview.com> wrote:
> This is an excerpt from the latest version perlfaq5.pod, which
> comes with the standard Perl distribution. These postings aim to
> reduce the number of repeated questions as well as allow the community
> to review and update the answers. The latest version of the complete
> perlfaq is athttp://faq.perl.org.
>
> --------------------------------------------------------------------
>
> 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.
>
> --------------------------------------------------------------------
>

Wasn't one of these one-liners included once?

perl -lne '}print $.;{' file # Abigail's trick
perl -lne 'END {print $.}' file

--
Charles DeRykus

[brian d foy]

In article
<48ffe7ef-f5da-4ec4...@u36g2000prn.googlegroups.com>,
C.DeRykus <der...@gmail.com> wrote:

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

> Wasn't one of these one-liners included once?
>
> perl -lne '}print $.;{' file # Abigail's trick
> perl -lne 'END {print $.}' file

Those seem like worthy additions. I'll add them to my queue.