RRDp(3) RRDtool RRDp(3) NNAAMMEE RRDp - Attach rrdtool from within a perl script via a set of pipes; SSYYNNOOPPSSIISS use RRRRDDpp RRRRDDpp::::ssttaarrtt _p_a_t_h _t_o _r_r_d_t_o_o_l _e_x_e_c_u_t_a_b_l_e RRRRDDpp::::ccmmdd _r_r_d_t_o_o_l _c_o_m_m_a_n_d_l_i_n_e $answer = RRRRDD::::rreeaadd $status = RRRRDD::::eenndd $$RRRRDDpp::::uusseerr, $$RRRRDDpp::::ssyyss, $$RRRRDDpp::::rreeaall DDEESSCCRRIIPPTTIIOONN With this module you can safely communicate with the rrdtool. After every RRRRDDpp::::ccmmdd you have to issue an RRRRDDpp::::rreeaadd command to get rrrrddttoooolls answer to your command. The answer is returned as a pointer, in order to speed things up. If the last command did not return any data, RRRRDDpp::::rreeaadd will return an undefined variable. If you import the PERFORMANCE variables into your namespace, you can access rrdtools internal performance measurements. use RRRRDDpp Load the RRDp::pipe module. RRRRDDpp::::ssttaarrtt _p_a_t_h _t_o _r_r_d_t_o_o_l _e_x_e_c_u_t_a_b_l_e start rrdtool. The argument must be the path to the rrdtool executable RRRRDDpp::::ccmmdd _r_r_d_t_o_o_l _c_o_m_m_a_n_d_l_i_n_e pass commands on to rrdtool. check the rrdtool documentation for more info on the rrdtool commands. $answer = RRRRDDpp::::rreeaadd read rrdtools response to your command. Note that the $answer variable will only contain a pointer to the returned data. The reason for this is, that rrdtool can potentially return quite excessive amounts of data and we don't want to copy this around in memory. So when you want to access the contents of $answer you have to use $$answer which dereferences the variable. $status = RRRRDDpp::::eenndd terminates rrdtool and returns rrdtools status ... $$RRRRDDpp::::uusseerr, $$RRRRDDpp::::ssyyss, $$RRRRDDpp::::rreeaall these variables will contain totals of the user time, system time and real time as seen by rrdtool. User time is the time rrdtool is running, System time is the time spend in system calls and real time is the total time rrdtool has been running. The difference between user + system and real is the time spent waiting for things like the hard disk and new input from the perl script. EEXXAAMMPPLLEE use RRDp; RRDp::start "/usr/local/bin/rrdtool"; RRDp::cmd qw(create demo.rrd --step 100 DS:in:GAUGE:100:U:U RRA:AVERAGE:0.5:1:10); $answer = RRDp::read; print $$answer; ($usertime,$systemtime,$realtime) = ($RRDp::user,$RRDp::sys,$RRDp::real); SSEEEE AALLSSOO For more information on how to use rrdtool, check the manpages. AAUUTTHHOORR Tobias Oetiker 1.0.50 2005-04-25 RRDp(3)