Here's the thing:

I've a log file. I need to count how many times a particular string appeared in that log file within the past 1 hour.

So I employed File::ReadBackwards for that purpose.

However, I get very weird results!

Judge for yourself, code (and output from it) below 

#!/usr/bin/perl

# Checks for proactive hits within the past hour

use File::ReadBackwards;
use POSIX "strftime";

my $success;
my $items;
my $earliest = POSIX::strftime( "%Y-%m-%d %H:%M:%S", localtime( time()
+ - 60 * 60 ) );

print "$earliest\n";

$bw = File::ReadBackwards->new( '/software/logs/CCASL/ccasl.log' ) or
                        die "can't read '/software/logs/CCASL/ccasl.lo
+g' $!" ;

while ( defined( my $log_line = $bw->readline() ) ) {


    last if $log_line lt $earliest;

    if ($log_line =~ /ProcessHTTPRequestImpl/) {
        print $log_line;
    }

}

[download]

Here's the output you get when you run it: 

[root@lpo-tomcat-09 ~]# prohits.pl
2007-07-10 12:17:22
2007-07-10 13:17:05,879 (rocessor23) INFO  [ProcessHTTPRequestImpl] Ca
+llOut Params: DREREFERENCE:6272332 catTag:10006 caller:rtr2_CAP1_1a w
+arp:true
2007-07-10 13:17:05,750 (rocessor16) INFO  [ProcessHTTPRequestImpl] Ca
+llOut Params: DREREFERENCE:6272334 catTag:10006 caller:rtp2_CAP3_1a w
+arp:true
2007-07-10 13:17:05,742 (rocessor24) INFO  [ProcessHTTPRequestImpl] Ca
+llOut Params: DREREFERENCE:6272326 catTag:10006 caller:rtr2_CAP1_1a w
+arp:true
2007-07-10 13:17:05,627 (rocessor16) INFO  [ProcessHTTPRequestImpl] Ca
+llOut Params: DREREFERENCE:6272259 catTag:10006 caller:rtp2_CAP4_1a w
+arp:true
[root@lpo-tomcat-09 ~]#

[download]

As you see, $earliest is set to the right string - one hour ago. But it only prints stuff that happened within the last minute, not last hour!

Any ideas?

In reply to Problem using File::ReadBackwards by vxp

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