1) If the file is short:

2) If the file is long, check out File::ReadBackwards

Thanks it works great.

I have been on many many forums and this Perl Monks is by far the best. Everytime I have posted, I get multiple responses and guidance form experts in a very quick amount of time!

Thanks again!!!

print "here is last line:  $lines[ -1 ]";
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use File::ReadBackwards;
my $bw = File::ReadBackwards->new( 'oratabtest.txt' ) or
                        die "can't read 'oratabtest.txt' $!" ;

while( my $line = $bw->readline) { print "Last line: $line"; last; }
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Eric

The "short path" is this:

open FILE, '<', $file or die("Can't read $file: $!");
my $lastline;
while (<FILE>) {
   $lastline = $_;
}
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Of course, you're still reading through the whole file, but at least you're not storing its whole contents in memory... as others have said, though, File::ReadBackwards is probably your best bet.

TMTOWTDI:

Re: Perl equivilant to tail -f

HTH,

so close ... so close

my $file = 'oratabtest.txt'
open FILE, "< $file" or die;
my @lines = <FILE>;
open FILE, "> $file" or die;
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Now the question is not how to get the last line of a file but the last element of an array (since you slurped the whole file into @lines).

ad 1) If you want to get the last element of an array you can use the index -1 or $#array_name: print $lines[-1]; or print $lines[$#lines];

ad 2) if you are only interested in the last line you don't need to store the whole file in an array. Just loop through the file and remember the line you've just read, until you arrive at the end and print the last line you've seen.

Of course if you know the file is huge you may need/want to do something more complex, using seek(), reading last N bytes of the file, checking there is a newline character in that and possibly read a bigger chunk ... but the question is whether it's worth the effort.

I see no mention to Tie::File. With this module, you can use your file as a Perl array.

use Tie::File;
tie @array, 'Tie::File', $filename or die $!;
print $array[-1];
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But remember: this will open your file in read/write mode, so any modifications you make in array will reflect on file's data. Use this way for read-only access:

use Tie::File;
use Fcntl 'O_RDONLY';
tie @array, 'Tie::File', $filename, mode => O_RDONLY
    or die $!;
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$lastLine = `tail -1 <fileName>`;
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