$ tac /var/log/rsync.log | perl -lane 'if(/received/){ print "$F[0] $F
+[1]"; exit }'
# Update 2017-04-21: compacting that a little bit:
$ tac /var/log/rsync.log | perl -lane 'if(/received/){print"@F[0,1]";e
+xit}'

[download]

Script (using File::ReadBackwards):

use warnings;
use strict;
use File::ReadBackwards;

die "Usage: $0 LOGFILE\n" unless @ARGV==1;
my $FILE = shift @ARGV;

my $bw = File::ReadBackwards->new($FILE)
    or die "Can't read $FILE: $!" ;
LINE: while(defined( my $line = $bw->readline )) {
    chomp($line);
    if ( $line =~ /received/ ) {
        my ($dt) = $line =~ /^([\d\/]+\s+[\d\:]+)\b/
            or die "Failed to parse date from: $line\n";
        print "$dt\n";
        last LINE;
    }
}
$bw->close;

[download]

Update: Credit to Discipulus for the inspiration of the first one-liner. Here's another one that scans the file forwards, like your original code does, but of course it'll be less efficient on larger files. For an explanation of }{ see the "Eskimo greeting" in perlsecret.

$ perl -lane '/received/ and $a="$F[0] $F[1]"}{print $a' /var/log/rsyn
+c.log

[download]

In reply to Re: one liner question by haukex
in thread one liner question by natxo

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