You are so right! SEEKing vs. line-by-line processing is wicked fast. For example test.pl script is a quick test script to determine timing to read the last 1024 bytes from the end of a 4GB file located on a remote server. 

use strict;
my $filename = shift;
my ( $curpos, $charsread, $buffer );
open(LOGFILE, "<", $filename) or die "can't open file: $!";

# Read last 1024 bytes of data.  Test this via
# read to -1024 bytes from EOF.
seek(LOGFILE, -1024, 2);
$curpos = tell(LOGFILE);
$charsread = read( LOGFILE, $buffer, 1024 );

print "Chars Read: $charsread\n";
print "Buffer:     >$buffer<\n";

close(LOGFILE);

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I ran as shown in next paragraph replacing my actual server name with "foo". I suspect most of you work with Perl on Unix but I'm loving Perl on Win32 and when I can use UNC file pathing as shown below it just tickles me that Perl is Win32 frienly in this way. Anyway, I digress. The result of below script run is the last 1024 bytes of the file is sub-second time. This is sooooooooooo fast! Thank you! 

test.pl \\foo\D$\MSSQL\BACKUP\DW\DW1_db_200701041904.BAK

[download]

In reply to Re^2: Extract new lines from log file by smithers
in thread Extract new lines from log file by smithers

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