(Go) Compress Large Binary File in Blocks

Compresses a large binary file in blocks. This example uses BeginCompressBytes, MoreCompressBytes, and EndCompressBytes.

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

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

    // Open a large binary file for reading.
    success := facSrc.OpenForRead("qa_data/bmp/big.bmp")
    if success != true {
        fmt.Println(facSrc.LastErrorText())
        facSrc.DisposeFileAccess()
        facDest.DisposeFileAccess()
        return
    }

    // If we compress in 64K chunks, find out how many blocks there will be.
    blockSize := 65536
    numBlocks := facSrc.GetNumBlocks(blockSize)

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

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

    i := 0
    for i < numBlocks {
        fileBytes = facSrc.ReadBlock(i,blockSize)
        if i == 0 {
            compressedBytes = compress.BeginCompressBytes(fileBytes)
        }
        else {
            compressedBytes = compress.MoreCompressBytes(fileBytes)
        }

        facDest.FileWrite(compressedBytes)

        i = i + 1
    }

    // At the very end, flush any remaining compressed bytes, if any.
    compressedBytes = compress.EndCompressBytes()
    facDest.FileWrite(compressedBytes)

    facSrc.FileClose()
    facDest.FileClose()

    fmt.Println("Finished compressing file.")

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