The RRDTool::OO module's graph method requires a file name in order to plot a graph (create a gif/png) I am trying to use this in a CGI, and would like to write to STDOUT, but cannot seem to figure out how to force this, or even if forcing it is possible. Setting 'image' to "-" results in:

malformed header from script. Bad header=GIF87a!!!: scriptname.cgi

When 'image' is "-" part of the gif prints before the HTTP header, and then the rest of the gif, which makes this even more bizzare, but explains the "Bad Header errror. Is making this module write to STDOUT possible? If so, how does one do it? Any thoughts? I'd really like to avoid Hitting the disk with a temp write,read. 
 

print "Content-type: image/gif\nExpires: 0\n\n";
$rrd->graph( image          => "-",
             vertical_label => 'My Salary',
                       draw => { thickness => 2,
                                 color     => 'FF0000',
                                 legend    => 'Salary over Time',
                        },
    );

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In reply to Tricking a filename argument to use STDOUT by fapestniegd

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