(Unicode C) Unzip Binary File to Stream

Demonstrates how to unzip a large binary file to a stream to allow the application to process the uncompressed bytes chunk by chunk.

Note: This example requires Chilkat v9.5.0.67 or greater.

Chilkat C/C++ Library Downloads
MS Visual C/C++ Linux/CentOS C/C++ Alpine Linux C/C++ MAC OS X C/C++	armhf/aarch64 C/C++ C++ Builder iOS C/C++ Android C/C++	Solaris C/C++ MinGW C/C++

#include <C_CkZipW.h>
#include <C_CkZipEntryW.h>
#include <C_CkStreamW.h>
#include <C_CkTaskW.h>
#include <C_CkFileAccessW.h>
#include <C_CkBinDataW.h>

void ChilkatSample(void)
    {
    HCkZipW zip;
    BOOL success;
    HCkZipEntryW entry;
    HCkStreamW dataStream;
    HCkTaskW unzipTask;
    HCkFileAccessW fac;
    HCkBinDataW bd;

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

    zip = CkZipW_Create();

    // First open a .zip.
    success = CkZipW_OpenZip(zip,L"qa_data/zips/big.zip");
    if (success != TRUE) {
        wprintf(L"%s\n",CkZipW_lastErrorText(zip));
        CkZipW_Dispose(zip);
        return;
    }

    // Get the entry to be unzipped to a stream..
    entry = CkZipW_GetEntryByIndex(zip,0);
    if (CkZipW_getLastMethodSuccess(zip) != TRUE) {
        wprintf(L"%s\n",CkZipW_lastErrorText(zip));
        CkZipW_Dispose(zip);
        return;
    }

    dataStream = CkStreamW_Create();

    unzipTask = CkZipEntryW_UnzipToStreamAsync(entry,dataStream);
    if (CkZipEntryW_getLastMethodSuccess(entry) != TRUE) {
        wprintf(L"%s\n",CkZipEntryW_lastErrorText(entry));
        CkZipEntryW_Dispose(entry);
        CkZipW_Dispose(zip);
        CkStreamW_Dispose(dataStream);
        return;
    }

    // Start the background unzip thread.
    CkTaskW_Run(unzipTask);

    // We'll read the uncompressed data chunk-by-chunk and write to an output file.
    fac = CkFileAccessW_Create();
    success = CkFileAccessW_OpenForWrite(fac,L"qa_output/out.dat");
    if (success != TRUE) {
        wprintf(L"%s\n",CkFileAccessW_lastErrorText(fac));
        CkZipEntryW_Dispose(entry);
        CkZipW_Dispose(zip);
        CkStreamW_Dispose(dataStream);
        CkFileAccessW_Dispose(fac);
        return;
    }

    // Read the stream.  (this is reading the unzipped file data)
    bd = CkBinDataW_Create();
    while (CkStreamW_getEndOfStream(dataStream) != TRUE) {
        // Get the next chunk of decompressed bytes.
        CkStreamW_ReadBd(dataStream,bd);
        // Do something with it..
        // In this simple example, we'll just write to the file.
        CkFileAccessW_FileWriteBd(fac,bd,0,0);
        // Clear for the next read.
        CkBinDataW_Clear(bd);
    }

    CkFileAccessW_FileClose(fac);

    CkZipEntryW_Dispose(entry);
    CkTaskW_Dispose(unzipTask);
    wprintf(L"Success.\n");


    CkZipW_Dispose(zip);
    CkStreamW_Dispose(dataStream);
    CkFileAccessW_Dispose(fac);
    CkBinDataW_Dispose(bd);

    }