(Go) Decompress Large Binary File in Blocks

Decompresses a large binary file in blocks. This example uses BeginDecompressBytes, MoreDecompressBytes, and EndDecompressBytes.

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    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    facSrc := chilkat.NewFileAccess()
    facDest := chilkat.NewFileAccess()

    // Open a previously compressed file for decompressing.
    // See Compress Large File in Blocks

    success := facSrc.OpenForRead("qa_data/bmp/compressedBmp.dat")
    if success != true {
        fmt.Println(facSrc.LastErrorText())
        facSrc.DisposeFileAccess()
        facDest.DisposeFileAccess()
        return
    }

    // If we compress in 32K chunks, find out how many blocks there will be.
    blockSize := 32768
    numBlocks := facSrc.GetNumBlocks(blockSize)

    // Open an output file for the decompressed data.
    success = facDest.OpenForWrite("qa_output/decompressed.bmp")
    if success != true {
        fmt.Println(facDest.LastErrorText())
        facSrc.DisposeFileAccess()
        facDest.DisposeFileAccess()
        return
    }

    compress := chilkat.NewCompression()
    compress.SetAlgorithm("deflate")

    i := 0
    for i < numBlocks {
        compressedBytes = facSrc.ReadBlock(i,blockSize)
        if i == 0 {
            decompressedBytes = compress.BeginDecompressBytes(compressedBytes)
        }
        else {
            decompressedBytes = compress.MoreDecompressBytes(compressedBytes)
        }

        facDest.FileWrite(decompressedBytes)

        i = i + 1
    }

    // At the very end, flush any remaining decompressed bytes, if any.
    decompressedBytes = compress.EndDecompressBytes()
    facDest.FileWrite(decompressedBytes)

    facSrc.FileClose()
    facDest.FileClose()

    fmt.Println("Finished decompressing file.")

    facSrc.DisposeFileAccess()
    facDest.DisposeFileAccess()
    compress.DisposeCompression()