Read the REST Response Body in Chunks

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Demonstrates Rest.ReadRespChunkBd, which reads the response body one chunk at a time, appending each chunk to a BinData. A return value of 0 signals the body is complete, while -1 indicates a read failure.

#include <C_CkRestW.h>
#include <C_CkStringBuilderW.h>
#include <C_CkBinDataW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkRestW rest;
    BOOL bTls;
    BOOL bAutoReconnect;
    int statusCode;
    HCkStringBuilderW sbError;
    HCkBinDataW bdBody;
    int chunkResult;

    success = FALSE;

    rest = CkRestW_Create();
    bTls = TRUE;
    bAutoReconnect = TRUE;
    success = CkRestW_Connect(rest,L"example.com",443,bTls,bAutoReconnect);
    if (success == FALSE) {
        wprintf(L"%s\n",CkRestW_lastErrorText(rest));
        CkRestW_Dispose(rest);
        return;
    }

    success = CkRestW_SendReqNoBody(rest,L"GET",L"/api/largefile");
    if (success == FALSE) {
        wprintf(L"%s\n",CkRestW_lastErrorText(rest));
        CkRestW_Dispose(rest);
        return;
    }

    statusCode = CkRestW_ReadResponseHeader(rest);
    if (statusCode < 0) {
        wprintf(L"%s\n",CkRestW_lastErrorText(rest));
        CkRestW_Dispose(rest);
        return;
    }

    //  Check for the expected success status code.  If the response is not 200, the body is likely
    //  error text formatted as JSON, XML, or HTML rather than the expected content.  In that case read
    //  the body as text, report it, and return.
    if (statusCode != 200) {
        sbError = CkStringBuilderW_Create();
        success = CkRestW_ReadRespSb(rest,sbError);
        if (success == FALSE) {
            wprintf(L"%s\n",CkRestW_lastErrorText(rest));
            CkRestW_Dispose(rest);
            CkStringBuilderW_Dispose(sbError);
            return;
        }

        wprintf(L"Request failed with status code %d\n",statusCode);
        wprintf(L"%s\n",CkStringBuilderW_getAsString(sbError));
        CkRestW_Dispose(rest);
        CkStringBuilderW_Dispose(sbError);
        return;
    }

    //  The status code is 200.  Read the response body in chunks, appending each chunk to the BinData.
    //  Each call waits until at least the requested number of bytes is available, unless the response
    //  ends first.  A return value of 0 means the final bytes were returned and the body is complete;
    //  -1 indicates a read failure.
    bdBody = CkBinDataW_Create();
    chunkResult = CkRestW_ReadRespChunkBd(rest,8192,bdBody);
    while (chunkResult > 0) {
        chunkResult = CkRestW_ReadRespChunkBd(rest,8192,bdBody);
    }

    if (chunkResult < 0) {
        wprintf(L"%s\n",CkRestW_lastErrorText(rest));
        CkRestW_Dispose(rest);
        CkStringBuilderW_Dispose(sbError);
        CkBinDataW_Dispose(bdBody);
        return;
    }

    wprintf(L"Received %d bytes.\n",CkBinDataW_getNumBytes(bdBody));


    CkRestW_Dispose(rest);
    CkStringBuilderW_Dispose(sbError);
    CkBinDataW_Dispose(bdBody);

    }