code: func injectRuntimeConfig(orig *NetworkConfig, rt *RuntimeConf) (*NetworkConfig, error) {
  	var err error
  
  	rc := make(map[string]interface{})
  	for capability, supported := range orig.Network.Capabilities {
  		if !supported {
  			continue
  		}
  		if data, ok := rt.CapabilityArgs[capability]; ok {
  			rc[capability] = data
  		}
  	}
  
  	if len(rc) > 0 {
  		orig, err = InjectConf(orig, map[string]interface{}{"runtimeConfig": rc})
  		if err != nil {
  			return nil, err
  		}
  	}
  
  	return orig, nil
  }
docs: // This function takes a libcni RuntimeConf structure and injects values into
  // a "runtimeConfig" dictionary in the CNI network configuration JSON that
  // will be passed to the plugin on stdin.
  //
  // Only "capabilities arguments" passed by the runtime are currently injected.
  // These capabilities arguments are filtered through the plugin's advertised
  // capabilities from its config JSON, and any keys in the CapabilityArgs
  // matching plugin capabilities are added to the "runtimeConfig" dictionary
  // sent to the plugin via JSON on stdin.  For example, if the plugin's
  // capabilities include "portMappings", and the CapabilityArgs map includes a
  // "portMappings" key, that key and its value are added to the "runtimeConfig"
  // dictionary to be passed to the plugin's stdin.