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         use RRDs;
         RRDs::last ...
         RRDs::info ...
         RRDs::create ...
         RRDs::update ...
         RRDs::graph ...
         RRDs::fetch ...
         RRDs::tune ...


       Calling Sequence

       This module accesses rrdtool functionality directly from
       within perl. The arguments to the functions listed in the
       SYNOPSIS are explained in the regular rrdtool documenta­
       tion. The commandline call

        rrdtool update mydemo.rrd --template in:out N:12:13

       gets turned into

        RRDs::update ("mydemo.rrd", "--template", "in:out", "N:12:13");

       Note that


       is also valid.

       Error Handling

       The RRD functions will not abort your program even when
       they can not make sense out of the arguments you fed them.

       The function RRDs::error should be called to get the error
       status after each function call. If RRDs::error does not
       return anything then the previous function has completed
       its task successfully.

        use RRDs;
        RRDs::update ("mydemo.rrd","N:12:13");
        my $ERR=RRDs::error;
        die "ERROR while updating mydemo.rrd: $ERR\n" if $ERR;

       Return Values

       The functions RRDs::last, RRDs::graph, RRDs::info and
       RRDs::fetch return their findings.

       RRDs::last returns a single INTEGER representing the last
       ues of the hash are the values of the properties.

        $hash = RRDs::info "example.rrd";
        foreach my $key (keys %$hash){
          print "$key = $$hash{$key}\n";

       RRDs::fetch is the most complex of the pack regarding
       return values. There are 4 values. Two normal integers, a
       pointer to an array and a pointer to a array of pointers.

         my ($start,$step,$names,$data) = RRDs::fetch ...
         print "Start:       ", scalar localtime($start), " ($start)\n";
         print "Step size:   $step seconds\n";
         print "DS names:    ", join (", ", @$names)."\n";
         print "Data points: ", $#$data + 1, "\n";
         print "Data:\n";
         foreach my $line (@$data) {
           print "  ", scalar localtime($start), " ($start) ";
           $start += $step;
           foreach my $val (@$line) {
             printf "%12.1f ", $val;
           print "\n";

       See the examples directory for more ways to use this


       If you are manipulating the TZ variable you should also
       call the posixs function tzset to initialize all internal
       state of the library for properly operating in the time­
       zone of your choice.

        use POSIX qw(tzset);
        $ENV{TZ} = 'CET';


       Tobias Oetiker <oetiker@ee.ethz.ch>

1.0.45                      2003-07-21                    RRDs(3)

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