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

[Jack Tavares]

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
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Email sent to me Thursday afternoon (PST) may not be viewed until Sunday
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