code: func labelIndex(labels *bpfLabels, lb string) uint32 {
  	var id uint32
  	for id = 0; id < uint32(len(*labels)); id++ {
  		if strings.EqualFold(lb, (*labels)[id].label) {
  			return id
  		}
  	}
  	*labels = append(*labels, bpfLabel{lb, 0xffffffff})
  	return id
  }
docs: // labelIndex returns the index for the label if it exists in the slice.
  // if it does not exist in the slice it appends the label lb to the end
  // of the slice and returns the index.