vendor/github.com/ulikunitz/xz/README.md

   1 # Package xz
   2
   3 This Go language package supports the reading and writing of xz
   4 compressed streams. It includes also a gxz command for compressing and
   5 decompressing data. The package is completely written in Go and doesn't
   6 have any dependency on any C code.
   7
   8 The package is currently under development. There might be bugs and APIs
   9 are not considered stable. At this time the package cannot compete with
  10 the xz tool regarding compression speed and size. The algorithms there
  11 have been developed over a long time and are highly optimized. However
  12 there are a number of improvements planned and I'm very optimistic about
  13 parallel compression and decompression. Stay tuned!
  14
  15 ## Using the API
  16
  17 The following example program shows how to use the API.
  18
  19 ```go
  20 package main
  21
  22 import (
  23     "bytes"
  24     "io"
  25     "log"
  26     "os"
  27
  28     "github.com/ulikunitz/xz"
  29 )
  30
  31 func main() {
  32     const text = "The quick brown fox jumps over the lazy dog.\n"
  33     var buf bytes.Buffer
  34     // compress text
  35     w, err := xz.NewWriter(&buf)
  36     if err != nil {
  37         log.Fatalf("xz.NewWriter error %s", err)
  38     }
  39     if _, err := io.WriteString(w, text); err != nil {
  40         log.Fatalf("WriteString error %s", err)
  41     }
  42     if err := w.Close(); err != nil {
  43         log.Fatalf("w.Close error %s", err)
  44     }
  45     // decompress buffer and write output to stdout
  46     r, err := xz.NewReader(&buf)
  47     if err != nil {
  48         log.Fatalf("NewReader error %s", err)
  49     }
  50     if _, err = io.Copy(os.Stdout, r); err != nil {
  51         log.Fatalf("io.Copy error %s", err)
  52     }
  53 }
  54 ```
  55
  56 ## Using the gxz compression tool
  57
  58 The package includes a gxz command line utility for compression and
  59 decompression.
  60
  61 Use following command for installation:
  62
  63     $ go get github.com/ulikunitz/xz/cmd/gxz
  64
  65 To test it call the following command.
  66
  67     $ gxz bigfile
  68
  69 After some time a much smaller file bigfile.xz will replace bigfile.
  70 To decompress it use the following command.
  71
  72     $ gxz -d bigfile.xz
  73