Clear the FTP Directory Listing Cache

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Demonstrates the Chilkat Ftp2.ClearDirCache method, which clears the cached listing for the current remote directory. It takes no arguments; the next indexed-listing call fetches a fresh listing from the server.

Background: The index-based directory API caches the listing the first time you read it, so repeated accessor calls avoid extra round trips. The trade-off is staleness: if the directory changes — files added or removed, whether by your own operations or another process — the cache still reflects the old state. ClearDirCache discards it so the next GetDirCount queries the server again.

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#include <C_CkFtp2.h>

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

    success = FALSE;

    //  Demonstrates the Ftp2.ClearDirCache method, which clears the cached listing for the current
    //  remote directory.  It takes no arguments and is a void method.

    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;
    }

    //  The first GetDirCount caches the listing.
    n = CkFtp2_GetDirCount(ftp);
    printf("Entries: %d\n",n);

    //  ... the remote directory changes (files added or removed by another process) ...

    //  Discard the cache so the next listing call fetches fresh data from the server.
    CkFtp2_ClearDirCache(ftp);

    n = CkFtp2_GetDirCount(ftp);
    printf("Entries after refresh: %d\n",n);

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



    CkFtp2_Dispose(ftp);

    }