forked from Shiloh/githaven
74 lines
1.9 KiB
Markdown
74 lines
1.9 KiB
Markdown
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# Package xz
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This Go language package supports the reading and writing of xz
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compressed streams. It includes also a gxz command for compressing and
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decompressing data. The package is completely written in Go and doesn't
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have any dependency on any C code.
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The package is currently under development. There might be bugs and APIs
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are not considered stable. At this time the package cannot compete with
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the xz tool regarding compression speed and size. The algorithms there
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have been developed over a long time and are highly optimized. However
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there are a number of improvements planned and I'm very optimistic about
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parallel compression and decompression. Stay tuned!
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## Using the API
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The following example program shows how to use the API.
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```go
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package main
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import (
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"bytes"
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"io"
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"log"
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"os"
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"github.com/ulikunitz/xz"
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)
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func main() {
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const text = "The quick brown fox jumps over the lazy dog.\n"
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var buf bytes.Buffer
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// compress text
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w, err := xz.NewWriter(&buf)
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if err != nil {
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log.Fatalf("xz.NewWriter error %s", err)
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}
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if _, err := io.WriteString(w, text); err != nil {
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log.Fatalf("WriteString error %s", err)
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}
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if err := w.Close(); err != nil {
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log.Fatalf("w.Close error %s", err)
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}
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// decompress buffer and write output to stdout
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r, err := xz.NewReader(&buf)
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if err != nil {
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log.Fatalf("NewReader error %s", err)
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}
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if _, err = io.Copy(os.Stdout, r); err != nil {
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log.Fatalf("io.Copy error %s", err)
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}
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}
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```
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## Using the gxz compression tool
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The package includes a gxz command line utility for compression and
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decompression.
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Use following command for installation:
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$ go get github.com/ulikunitz/xz/cmd/gxz
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To test it call the following command.
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$ gxz bigfile
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After some time a much smaller file bigfile.xz will replace bigfile.
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To decompress it use the following command.
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$ gxz -d bigfile.xz
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