sub mylog {
    my (@fields) = @_;
    my $entry = join ( "|", @fields );
    open my $fh, ">>" . &MYLOG or die "can't open " . &MYLOG . ": $!";
    flock $fh, LOCK_EX;
    print $fh $entry . "\n";
    close $fh;
}

##</code><code>##

#untested!
open my $fh, "|bin/rotatelogs /var/logs/%y_%m_%d_%H_%M_%S 14400" or die "can't open pipe to rotatelogs: $!";