Operations such as getting a file or changing the current directory can only be performed sequentially per session. Consequently, the corresponding methods are SYNC methods and hence are serialized between threads. If concurrent operations against the same FTP server are required in an application, a new connection must be initiated from another thread using a separate FTPClient object.
Class FTPClient() Professional
Class function of the FTPClient class
Instances of the FTPClient class are used to access an FTP server via the File Transfer Protocol. This communication protocol allows for exchanging the contents of arbitrary files between a client computer and a remote server in the Internet. A prerequisite for successfully using the FTPClient class is that Username and Password for accessing an FTP server are known. A connection to an FTP server fails without proper authentication.
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