[rrd-users] getting MAX, LAST VDEFs without generating graph from C library

[Jack Tavares]

Is that for inspiration on

1. is there another way to do this

or

2. how do I do this with a c function?

I assume #2 :-)

Thanks
 

> -----Original Message-----
> From: Tobias Oetiker [mailto:tobi at oetiker.ch] 
> Sent: Wednesday, February 13, 2008 4:17 AM
> To: Jack Tavares
> Cc: rrd-users at lists.oetiker.ch
> Subject: Re: [rrd-users] getting MAX, LAST VDEFs without 
> generating graph from C library
> 
> Hi Jack,
> 
> check out rrd_tool.c for inspiration
> 
> cheers
> tobi
> 
> Today Jack Tavares wrote:
> 
> > Hello all
> >
> > I have some existing rrdfile with some data in them.
> >
> > I was reading  about the VDEF capabilities of the rrdgraph
> > command.
> >
> > I am using the c library functions to manipulate the rrd files.
> >
> > I want the MAX and LAST from a graph, but I don't want the graph.
> >
> > At the command line I would do:
> >
> > rrdtool graph xy.png -aPNG
> > DEF:curclientconns=/var/rrd/connections:curclientconns:AVERAGE
> > VDEF:connsmax=curclientconns,MAXIMUM 
> VDEF:connslast=curclientconns,LAST
> > PRINT:connslast:"last=%12.0lf" PRINT:connsmax:"max=%12.0lf"
> >
> > This prints to stdout.
> >
> > If I am calling rrd_graph() C function, how do I get this data?
> >
> >
> > Is there a better way to do this? I m very open to 
> suggestions, but I
> > have to stick with the C library calls.
> >
> > Ok, one more question:
> > I dont see any API docs for theC library on the web site. 
> Are there any?
> >
> > Thanks again
> >
> > --
> > Jack Tavares
> > Reminder: I am at GMT+2, 10 hours AHEAD of Seattle.
> > My workweek is Sunday-Thursday.
> > Email sent to me Thursday afternoon (PST) may not be viewed 
> until Sunday
> > morning (GMT+2).
> >
> >
> >
> 
> -- 
> Tobi Oetiker, OETIKER+PARTNER AG, Aarweg 15 CH-4600 Olten
> http://it.oetiker.ch tobi at oetiker.ch ++41 62 213 9902
>