C++

Clear the FTP Directory Listing Cache

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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C++

#include <CkFtp2.h>

void ChilkatSample(void)
    {
    bool 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.

    CkFtp2 ftp;

    ftp.put_Hostname("ftp.example.com");
    ftp.put_Username("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.
    ftp.put_Password("myPassword");

    success = ftp.Connect();
    if (success == false) {
        std::cout << ftp.lastErrorText() << "\r\n";
        return;
    }

    success = ftp.ChangeRemoteDir("public_html");
    if (success == false) {
        std::cout << ftp.lastErrorText() << "\r\n";
        return;
    }

    //  The first GetDirCount caches the listing.
    int n = ftp.GetDirCount();
    std::cout << "Entries: " << n << "\r\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.
    ftp.ClearDirCache();

    n = ftp.GetDirCount();
    std::cout << "Entries after refresh: " << n << "\r\n";

    success = ftp.Disconnect();
    if (success == false) {
        std::cout << ftp.lastErrorText() << "\r\n";
        return;
    }
    }