Re: FIFO logfile done with flat file?

[clintp]

You could do it with a flat file. There's lots of ways. One script I had used a simple DBM file and went something like this (hope this is cut down right):

{
        use Fcntl qw(:flock);
        my %h;
        my $size=5;

        sub ringopen {
                open(F, ">ring.lock") || die;
                flock(F, LOCK_EX);
                dbmopen(%h, "ring", 0666) || die;
        }
        sub ringclose { dbmclose(%h); close(F); }
        sub ringadd {
                ringopen();
                local $_=$h{next};
                delete $h{$_-$size} if (defined $_);
                $h{$h{next}++}=$_[0];
                ringclose();
        }
        sub ringdump {
                ringopen();
                my @a=sort { $a <=> $b } 
                          grep /^\d+$/, keys %h;
                @a=@h{@a};
                ringclose();
                return @a;
        }
}

And you used it like this:

for(0..9, 'a'..'z') {
        ringadd($_);
}
print ringdump();

To initialize the ring buffer, remove the ring* files.

YMMV, TIMTOWDI, etc..