Enable FTP MODE Z Compression

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Demonstrates the Chilkat Ftp2.SetModeZ method, which enables MODE Z compression for subsequent data connections. It takes no arguments. Call it after connecting and only when the HasModeZ property is true.

Background: MODE Z compresses data on the fly (using zlib) as it crosses the wire, which can meaningfully speed up transfers of compressible content — text, HTML, logs — over a slow link. It is a server extension, so check HasModeZ first and expect it to be unavailable on many servers. There is little benefit for already-compressed data such as images or archives, where the CPU cost of compression buys almost nothing.

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#include <C_CkFtp2.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkFtp2 ftp;

    success = FALSE;

    //  Demonstrates the Ftp2.SetModeZ method, which enables MODE Z compression for subsequent data
    //  connections.  It takes no arguments.  Call it after connecting, and only when the HasModeZ
    //  property indicates the server supports it.

    ftp = CkFtp2_Create();

    CkFtp2_putHostname(ftp,"ftp.example.com");
    CkFtp2_putUsername(ftp,"myFtpLogin");

    //  Normally you would not hard-code the password in source.  You should instead obtain it
    //  from an interactive prompt, environment variable, or a secrets vault.
    CkFtp2_putPassword(ftp,"myPassword");

    success = CkFtp2_Connect(ftp);
    if (success == FALSE) {
        printf("%s\n",CkFtp2_lastErrorText(ftp));
        CkFtp2_Dispose(ftp);
        return;
    }

    success = CkFtp2_ChangeRemoteDir(ftp,"public_html");
    if (success == FALSE) {
        printf("%s\n",CkFtp2_lastErrorText(ftp));
        CkFtp2_Dispose(ftp);
        return;
    }

    //  Only enable compression if the server advertises MODE Z support.
    if (CkFtp2_getHasModeZ(ftp)) {
        success = CkFtp2_SetModeZ(ftp);
        if (success == FALSE) {
            printf("%s\n",CkFtp2_lastErrorText(ftp));
            CkFtp2_Dispose(ftp);
            return;
        }

        printf("MODE Z compression enabled.\n");
    }
    else {
        printf("The server does not support MODE Z.\n");
    }

    //  Subsequent uploads, downloads, and listings are transferred compressed.

    success = CkFtp2_Disconnect(ftp);
    if (success == FALSE) {
        printf("%s\n",CkFtp2_lastErrorText(ftp));
        CkFtp2_Dispose(ftp);
        return;
    }



    CkFtp2_Dispose(ftp);

    }