be sure to try ikegami's method .. it does seem that '-' as the image name should work. Reference: RRDtool - rrdgraph (Make also check RRDTool::OO's source to see how directly it calls rrdgraph)

In reply to Re: Tricking a filename argument to use STDOUT by davidrw
in thread Tricking a filename argument to use STDOUT by fapestniegd

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