Function untargz

vg/example_test.go:85–113

(name string, r io.Reader)

}

func untargz(name string, r io.Reader) ([]byte, error) {
	gr, err := gzip.NewReader(r)
	if err != nil {
		return nil, fmt.Errorf("could not create gzip reader: %v", err)
	}
	defer gr.Close()

	tr := tar.NewReader(gr)
	for {
		hdr, err := tr.Next()
		if err != nil {
			if err == io.EOF {
				return nil, fmt.Errorf("could not find %q in tar archive", name)
			}
			return nil, fmt.Errorf("could not extract header from tar archive: %v", err)
		}

		if hdr == nil || hdr.Name != name {
			continue
		}

		buf := new(bytes.Buffer)
		_, err = io.Copy(buf, tr)
		if err != nil {
			return nil, fmt.Errorf("could not extract %q file from tar archive: %v", name, err)
		}
		return buf.Bytes(), nil
	}
}

func Example_inMemoryCanvas() {
	p := plot.New()