TFTPClient Component

Properties Methods Events Config Settings Errors

The TFTPClient component is used to exchange files with TFTP servers via the TFTP protocol defined in RFC 783.

Syntax

IPWorks.Tftpclient

Remarks

To use the component, first specify the TFTPServer, then a LocalFile and a RemoteFile, and then call GetFile or PutFile. The Transfer event shows the progress of the transfer.

Potential transmission errors and packet loss are managed by the Timeout property which controls the maximum time to wait for a response from the server, and the MaxRetransmits property which specifies how many times to resend a failed packet before giving up.

Property List

The following is the full list of the properties of the component with short descriptions. Click on the links for further details.


Idle	The current status of the component.
LocalFile	The file on the local host to transfer the data to/from.
LocalHost	The name of the local host or user-assigned IP interface through which connections are initiated or accepted.
MaxRetransmits	The number of times to retry sending a failed packet before disconnecting.
RemoteFile	The file on the remote host.
RetransmitTimeout	Maximum time in seconds to wait for a reply packet from the server before retransmitting the last packet.
TFTPPort	The UDP port where the remote TFTP server is listening.
TFTPServer	The address of the TFTP server to exchange files with.
Timeout	A timeout for the component.

Method List

The following is the full list of the methods of the component with short descriptions. Click on the links for further details.


config	Sets or retrieves a configuration setting.
doEvents	Processes events from the internal message queue.
getFile	Download a RemoteFile from the TFTP server.
interrupt	Interrupt the current method.
putFile	Upload a file specified by LocalFile to the TFTP server.
reset	Reset the component.
setDownloadStream	Sets the stream to which the downloaded data from the server will be written.
setUploadStream	Sets the stream to be uploaded to the server.

Event List

The following is the full list of the events fired by the component with short descriptions. Click on the links for further details.


EndTransfer	This event is fired when a file finishes downloading or uploading.
Error	Fired when information is available about errors during data delivery.
StartTransfer	This event fires when a file starts downloading or uploading.
Transfer	This event is fired during the file download or upload.

Config Settings

The following is a list of config settings for the component with short descriptions. Click on the links for further details.


BlockSize	Determines the block size that will be used when transferring a file.
CloseStreamAfterTransfer	If true, the component will close the upload or download stream after the transfer.
TransferMode	Determines the transfer mode that will be used when transferring a file.
CaptureIPPacketInfo	Used to capture the packet information.
DelayHostResolution	Whether the hostname is resolved when RemoteHost is set.
DestinationAddress	Used to get the destination address from the packet information.
DontFragment	Used to set the Don't Fragment flag of outgoing packets.
LocalHost	The name of the local host through which connections are initiated or accepted.
LocalPort	The port in the local host where the component binds.
MaxPacketSize	The maximum length of the packets that can be received.
QOSDSCPValue	Used to specify an arbitrary QOS/DSCP setting (optional).
QOSTrafficType	Used to specify QOS/DSCP settings (optional).
ShareLocalPort	If set to True, allows more than one instance of the component to be active on the same local port.
UseConnection	Determines whether to use a connected socket.
UseIPv6	Whether or not to use IPv6.
AbsoluteTimeout	Determines whether timeouts are inactivity timeouts or absolute timeouts.
FirewallData	Used to send extra data to the firewall.
InBufferSize	The size in bytes of the incoming queue of the socket.
OutBufferSize	The size in bytes of the outgoing queue of the socket.
BuildInfo	Information about the product's build.
GUIAvailable	Whether or not a message loop is available for processing events.
LicenseInfo	Information about the current license.
MaskSensitive	Whether sensitive data is masked in log messages.
UseDaemonThreads	Whether threads created by the component are daemon threads.
UseInternalSecurityAPI	Whether or not to use the system security libraries or an internal implementation.

Idle Property (TFTPClient Component)

The current status of the component.

Syntax


public boolean isIdle();

Default Value

True

Remarks

Idle will be False if the component is currently busy (communicating and/or waiting for an answer), and True at all other times.

This property is read-only.

LocalFile Property (TFTPClient Component)

The file on the local host to transfer the data to/from.

Syntax


public String getLocalFile();


public void setLocalFile(String localFile);

Default Value

Remarks

If GetFile is called, and LocalFile already exists, it is overwritten. If PutFile is called, LocalFile must point to a valid file, or an error will be returned.

LocalHost Property (TFTPClient Component)

The name of the local host or user-assigned IP interface through which connections are initiated or accepted.

Syntax


public String getLocalHost();


public void setLocalHost(String localHost);

Default Value

Remarks

The LocalHost property contains the name of the local host as obtained by the gethostname() system call, or if the user has assigned an IP address, the value of that address.

In multi-homed hosts (machines with more than one IP interface) setting LocalHost to the value of an interface will make the component initiate connections (or accept in the case of server components) only through that interface.

If the component is connected, the LocalHost property shows the IP address of the interface through which the connection is made in internet dotted format (aaa.bbb.ccc.ddd). In most cases, this is the address of the local host, except for multi-homed hosts (machines with more than one IP interface).

NOTE: LocalHost is not persistent. You must always set it in code, and never in the property window.

MaxRetransmits Property (TFTPClient Component)

The number of times to retry sending a failed packet before disconnecting.

Syntax


public int getMaxRetransmits();


public void setMaxRetransmits(int maxRetransmits);

Default Value

Remarks

This property allows you to specify the number of times that you would like to try re-sending the last data packet if the original packet fails.

The RetransmitTimeout determines the wait time (in seconds) between successive retransmissions.

The default value for the MaxRetransmits property is 3.

RemoteFile Property (TFTPClient Component)

The file on the remote host.

Syntax


public String getRemoteFile();


public void setRemoteFile(String remoteFile);

Default Value

Remarks

When the GetFile is called, this must be a valid file on the TFTPServer.

RetransmitTimeout Property (TFTPClient Component)

Maximum time in seconds to wait for a reply packet from the server before retransmitting the last packet.

Syntax


public int getRetransmitTimeout();


public void setRetransmitTimeout(int retransmitTimeout);

Default Value

Remarks

Please refer to the MaxRetransmits property for the number of retransmit efforts before an error is returned.

The default value for the RetransmitTimeout is 5 seconds.

TFTPPort Property (TFTPClient Component)

The UDP port where the remote TFTP server is listening.

Syntax


public int getTFTPPort();


public void setTFTPPort(int TFTPPort);

Default Value

Remarks

The TFTPPort is the UDP port on the TFTPServer to send TFTP requests to.

This property is not available at design time.

TFTPServer Property (TFTPClient Component)

The address of the TFTP server to exchange files with.

Syntax


public String getTFTPServer();


public void setTFTPServer(String TFTPServer);

Default Value

Remarks

To be able to transfer file via TFTP, the remote host must be running TFTP services on port TFTPPort (default 69).

Example (Get a File)

TFTPControl.TFTPServer = "MyServer" TFTPControl.LocalFile = "C:\filename.txt" TFTPControl.RemoteFile = "/remotefile.txt" TFTPControl.GetFile()

Timeout Property (TFTPClient Component)

A timeout for the component.

Syntax


public int getTimeout();


public void setTimeout(int timeout);

Default Value

Remarks

If the Timeout property is set to 0, all operations will run uninterrupted until successful completion or an error condition is encountered.

If Timeout is set to a positive value, the component will wait for the operation to complete before returning control.

The component will use DoEvents to enter an efficient wait loop during any potential waiting period, making sure that all system events are processed immediately as they arrive. This ensures that the host application does not "freeze" and remains responsive.

If Timeout expires, and the operation is not yet complete, the component throws an exception.

Please note that by default, all timeouts are inactivity timeouts, i.e. the timeout period is extended by Timeout seconds when any amount of data is successfully sent or received.

The default value for the Timeout property is 60 seconds.

Config Method (Tftpclient Component)

Sets or retrieves a configuration setting.

Syntax

public String config(String configurationString);

Remarks

Config is a generic method available in every component. It is used to set and retrieve configuration settings for the component.

These settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the component, access to these internal properties is provided through the Config method.

To set a configuration setting named PROPERTY, you must call Config("PROPERTY=VALUE"), where VALUE is the value of the setting expressed as a string. For boolean values, use the strings "True", "False", "0", "1", "Yes", or "No" (case does not matter).

To read (query) the value of a configuration setting, you must call Config("PROPERTY"). The value will be returned as a string.

DoEvents Method (Tftpclient Component)

Processes events from the internal message queue.

Syntax

public void doEvents();

Remarks

When DoEvents is called, the component processes any available events. If no events are available, it waits for a preset period of time, and then returns.

GetFile Method (Tftpclient Component)

Download a RemoteFile from the TFTP server.

Syntax

public void getFile();

Remarks

The remote file specified by RemoteFile is downloaded to the local file specified by LocalFile, or it is retrieved through the Transfer event, if the LocalFile property is "" (empty string).

Example (Get a File)

TFTPControl.TFTPServer = "MyServer" TFTPControl.LocalFile = "C:\filename.txt" TFTPControl.RemoteFile = "/remotefile.txt" TFTPControl.GetFile()

Interrupt Method (Tftpclient Component)

Interrupt the current method.

Syntax

public void interrupt();

Remarks

If there is no method in progress, Interrupt simply returns, doing nothing.

PutFile Method (Tftpclient Component)

Upload a file specified by LocalFile to the TFTP server.

Syntax

public void putFile();

Remarks

The local file specified by LocalFile is uploaded to the remote file specified by RemoteFile.

Example (Put a File)

TFTPControl.TFTPServer = "MyServer" TFTPControl.LocalFile = "C:\filename.txt" TFTPControl.RemoteFile = "/remotefile.txt" TFTPControl.PutFile()

Reset Method (Tftpclient Component)

Reset the component.

Syntax

public void reset();

Remarks

This method will reset the component's properties to their default values.

SetDownloadStream Method (Tftpclient Component)

Sets the stream to which the downloaded data from the server will be written.

Syntax

public void setDownloadStream(java.io.OutputStream downloadStream);

Remarks

If a download stream is set before the GetFile method is called, the downloaded data will be written to the stream. The stream should be open and normally set to position 0. The component will automatically close this stream if CloseStreamAfterTransfer is set to true (default). If the stream is closed, you will need to call SetDownloadStream again before calling GetFile again. The downloaded content will be written starting at the current position in the stream.

Note: SetDownloadStream and LocalFile will reset the other.

SetUploadStream Method (Tftpclient Component)

Sets the stream to be uploaded to the server.

Syntax

public void setUploadStream(java.io.InputStream uploadStream);

Remarks

If an upload stream is set before the PutFile method is called, the content of the stream will be read by the component and uploaded to the server; The stream should be open and normally set to position 0. The component will automatically close this stream if CloseStreamAfterTransfer is set to true (default). If the stream is closed, you will need to call SetUploadStream again before calling PutFile again. The content of the stream will be read from the current position all the way to the end.

Note: SetUploadStream and LocalFile will reset the other.

EndTransfer Event (Tftpclient Component)

This event is fired when a file finishes downloading or uploading.

Syntax

public class DefaultTftpclientEventListener implements TftpclientEventListener {
  ...
  public void endTransfer(TftpclientEndTransferEvent e) {}
  ...
}

public class TftpclientEndTransferEvent {
  public int direction;

}

Remarks

The EndTransfer event fires when a Data Interface connection is closed. This occurs when the file finishes transferring or a directory listing is finished.

The Direction parameter shows whether the client (0) or the server (1) is sending the data.

Error Event (Tftpclient Component)

Fired when information is available about errors during data delivery.

Syntax

public class DefaultTftpclientEventListener implements TftpclientEventListener {
  ...
  public void error(TftpclientErrorEvent e) {}
  ...
}

public class TftpclientErrorEvent {
  public int errorCode;

  public String description;

}

Remarks

The Error event is fired in case of exceptional conditions during message processing. Normally the component throws an exception.

The ErrorCode parameter contains an error code, and the Description parameter contains a textual description of the error. For a list of valid error codes and their descriptions, please refer to the Error Codes section.

StartTransfer Event (Tftpclient Component)

This event fires when a file starts downloading or uploading.

Syntax

public class DefaultTftpclientEventListener implements TftpclientEventListener {
  ...
  public void startTransfer(TftpclientStartTransferEvent e) {}
  ...
}

public class TftpclientStartTransferEvent {
  public int direction;

}

Remarks

The StartTransfer event fires when a Data Interface connection is created. This is when the file starts transferring or a directory listing is started.

The Direction parameter shows whether the client (0) or the server (1) is sending the data.

Transfer Event (Tftpclient Component)

This event is fired during the file download or upload.

Syntax

public class DefaultTftpclientEventListener implements TftpclientEventListener {
  ...
  public void transfer(TftpclientTransferEvent e) {}
  ...
}

public class TftpclientTransferEvent {
  public int direction;

  public long bytesTransferred;

  public int percentDone;

  public byte[] text;

}

Remarks

One or more Transfer events are fired during file transfer. The BytesTransferred parameter shows the number of bytes transferred since the beginning of the transfer.

Text contains the portion of the file data being delivered.

The Direction parameter shows whether the client (0) or the server (1) is sending the data.

The PercentDone parameter shows the progress of the transfer in the corresponding direction. If PercentDone can not be calculated the value will be -1.

Note: Events are not re-entrant. Performing time-consuming operations within this event will prevent it from firing again in a timely manner and may affect overall performance.

Config Settings (Tftpclient Component)

The component accepts one or more of the following configuration settings. Configuration settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the component, access to these internal properties is provided through the Config method.

TFTPClient Config Settings

BlockSize: Determines the block size that will be used when transferring a file.

Set this to the number of bytes the block should be. This uses the blocksize option as defined in RFC 2348. The default is 512.

CloseStreamAfterTransfer: If true, the component will close the upload or download stream after the transfer.

This setting determines whether the input or output stream is closed after the transfer completes. When set to True (default), all streams will be closed after a transfer is completed. In order to keep streams open after the transfer of data, set this to False. the default value is True.

TransferMode: Determines the transfer mode that will be used when transferring a file.

Available modes:


Value	Description
0 (default)	Binary (Octet)
1	Ascii (Netascii)

UDP Config Settings

CaptureIPPacketInfo: Used to capture the packet information.

If this is set to true, the component will capture the IP packet information.

The default value for this setting is False.

Note: This setting is only available in Windows.

DelayHostResolution: Whether the hostname is resolved when RemoteHost is set.

This setting specifies whether a hostname is resolved immediately when RemoteHost is set. If true the component will resolve the hostname and the IP address will be present in the RemoteHost property. If false, the hostname is not resolved until needed by the component when a method to connect or send data is called. If desired, ResolveRemoteHost may called to manually resolve the value in RemoteHost at any time.

The default value is false.

DestinationAddress: Used to get the destination address from the packet information.

If CaptureIPPacketInfo is set to true, then this will be populated with the packet's destination address when a packet is received. This information will be accessible in the DataIn event.

Note: This setting is only available in Windows.

DontFragment: Used to set the Don't Fragment flag of outgoing packets.

When set to True, packets sent by the component will have the Don't Fragment flag set. The default value is False.

LocalHost: The name of the local host through which connections are initiated or accepted.

The LocalHost setting contains the name of the local host as obtained by the gethostname() system call, or if the user has assigned an IP address, the value of that address.

If the component is connected, the LocalHost setting shows the IP address of the interface through which the connection is made in internet dotted format (aaa.bbb.ccc.ddd). In most cases, this is the address of the local host, except for multi-homed hosts (machines with more than one IP interface).

LocalPort: The port in the local host where the component binds.

This must be set before a connection is attempted. It instructs the component to bind to a specific port (or communication endpoint) in the local machine.

Setting this to 0 (default) enables the system to choose a port at random. The chosen port will be shown by LocalPort after the connection is established.

LocalPort cannot be changed once a connection is made. Any attempt to set this when a connection is active will generate an error.

This; setting is useful when trying to connect to services that require a trusted port in the client side. An example is the remote shell (rsh) service in UNIX systems.

MaxPacketSize: The maximum length of the packets that can be received.

This setting specifies the maximum size of the datagrams that the component will accept without truncation.

QOSDSCPValue: Used to specify an arbitrary QOS/DSCP setting (optional).

UseConnection must be True to use this setting. This option allows you to specify an arbitrary DSCP value between 0 and 63. The default is 0. When set to the default value the component will not set a DSCP value.

Note: This setting uses the qWAVE API is only available on Windows 7, Windows Server 2008 R2, and later.

QOSTrafficType: Used to specify QOS/DSCP settings (optional).

UseConnection must be True to use this setting. You may specify either the text or integer values: BestEffort (0), Background (1), ExcellentEffort (2), AudioVideo (3), Voice (4), and Control (5).

Note: This setting uses the qWAVE API which is only available on Windows Vista and Windows Server 2008 or above.

Note: QOSTrafficType must be set before setting Active to true.

ShareLocalPort: If set to True, allows more than one instance of the component to be active on the same local port.

This option must be set before the component is activated through the Active property or it will have no effect.

The default value for this setting is False.

UseConnection: Determines whether to use a connected socket.

UseConnection specifies whether the component should use a connected socket or not. The connection is defined as an association in between the local address/port and the remote address/port. As such, this is not a connection in the traditional TCP sense. What it means is only that the component will send and receive data only to and from the specified destination.

The default value for this setting is False.

UseIPv6: Whether or not to use IPv6.

By default, the component expects an IPv4 address for local and remote host properties, and will create an IPv4 socket. To use IPv6 instead, set this to True.

Socket Config Settings

AbsoluteTimeout: Determines whether timeouts are inactivity timeouts or absolute timeouts.

If AbsoluteTimeout is set to True, any method which does not complete within Timeout seconds will be aborted. By default, AbsoluteTimeout is False, and the timeout is an inactivity timeout.

Note: This option is not valid for UDP ports.

FirewallData: Used to send extra data to the firewall.

When the firewall is a tunneling proxy, use this property to send custom (additional) headers to the firewall (e.g. headers for custom authentication schemes).

InBufferSize: The size in bytes of the incoming queue of the socket.

This is the size of an internal queue in the TCP/IP stack. You can increase or decrease its size depending on the amount of data that you will be receiving. Increasing the value of the InBufferSize setting can provide significant improvements in performance in some cases.

Some TCP/IP implementations do not support variable buffer sizes. If that is the case, when the component is activated the InBufferSize reverts to its defined size. The same happens if you attempt to make it too large or too small.

OutBufferSize: The size in bytes of the outgoing queue of the socket.

This is the size of an internal queue in the TCP/IP stack. You can increase or decrease its size depending on the amount of data that you will be sending. Increasing the value of the OutBufferSize setting can provide significant improvements in performance in some cases.

Some TCP/IP implementations do not support variable buffer sizes. If that is the case, when the component is activated the OutBufferSize reverts to its defined size. The same happens if you attempt to make it too large or too small.

Base Config Settings

BuildInfo: Information about the product's build.

When queried, this setting will return a string containing information about the product's build.

GUIAvailable: Whether or not a message loop is available for processing events.

In a GUI-based application, long-running blocking operations may cause the application to stop responding to input until the operation returns. The component will attempt to discover whether or not the application has a message loop and, if one is discovered, it will process events in that message loop during any such blocking operation.

In some non-GUI applications, an invalid message loop may be discovered that will result in errant behavior. In these cases, setting GUIAvailable to false will ensure that the component does not attempt to process external events.

LicenseInfo: Information about the current license.

When queried, this setting will return a string containing information about the license this instance of a component is using. It will return the following information:

Product: The product the license is for.
Product Key: The key the license was generated from.
License Source: Where the license was found (e.g., RuntimeLicense, License File).
License Type: The type of license installed (e.g., Royalty Free, Single Server).
Last Valid Build: The last valid build number for which the license will work.

MaskSensitive: Whether sensitive data is masked in log messages.

In certain circumstances it may be beneficial to mask sensitive data, like passwords, in log messages. Set this to true to mask sensitive data. The default is true.

This setting only works on these components: AS3Receiver, AS3Sender, Atom, Client(3DS), FTP, FTPServer, IMAP, OFTPClient, SSHClient, SCP, Server(3DS), Sexec, SFTP, SFTPServer, SSHServer, TCPClient, TCPServer.

UseDaemonThreads: Whether threads created by the component are daemon threads.

If set to True (default), when the component creates a thread, the thread's Daemon property will be explicitly set to True. When set to False, the component will not set the Daemon property on the created thread. The default value is True.

UseInternalSecurityAPI: Whether or not to use the system security libraries or an internal implementation.

When set to false, the component will use the system security libraries by default to perform cryptographic functions where applicable.

Setting this configuration setting to true tells the component to use the internal implementation instead of using the system security libraries.

This setting is set to false by default on all platforms.

Trappable Errors (Tftpclient Component)

TFTPClient Errors


	122 Packet too large.
	123 Wrong response type from server.
	124 Server error. Description contains detailed information.
	125 Invalid server response.
	126 A valid LocalFile must be provided for PUT operations.
	127 Can't open local file.
	128 Can't write to local file.
	129 Can't read local file.
	130 Busy performing the current transfer.
	301 Timeout while waiting for server.
	305 Server error.
	306 Wrong or invalid response type received from server.
	307 Invalid response from server.

UDP Errors


	104 UDP is already Active.
	106 You cannot change the LocalPort while the component is Active.
	107 You cannot change the LocalHost at this time. A connection is in progress.
	109 The component must be Active for this operation.
	112 Cannot change MaxPacketSize while the component is Active.
	113 Cannot change ShareLocalPort option while the component is Active.
	114 Cannot change RemoteHost when UseConnection is set and the component Active.
	115 Cannot change RemotePort when UseConnection is set and the component is Active.
	116 RemotePort can't be zero when UseConnection is set. Please specify a valid service port number.
	117 Cannot change UseConnection while the component is Active.
	118 Message can't be longer than MaxPacketSize.
	119 Message too short.
	434 Unable to convert string to selected CodePage

SSL Errors


	270 Cannot load specified security library.
	271 Cannot open certificate store.
	272 Cannot find specified certificate.
	273 Cannot acquire security credentials.
	274 Cannot find certificate chain.
	275 Cannot verify certificate chain.
	276 Error during handshake.
	280 Error verifying certificate.
	281 Could not find client certificate.
	282 Could not find server certificate.
	283 Error encrypting data.
	284 Error decrypting data.

TCP/IP Errors


	10004 [10004] Interrupted system call.
	10009 [10009] Bad file number.
	10013 [10013] Access denied.
	10014 [10014] Bad address.
	10022 [10022] Invalid argument.
	10024 [10024] Too many open files.
	10035 [10035] Operation would block.
	10036 [10036] Operation now in progress.
	10037 [10037] Operation already in progress.
	10038 [10038] Socket operation on non-socket.
	10039 [10039] Destination address required.
	10040 [10040] Message too long.
	10041 [10041] Protocol wrong type for socket.
	10042 [10042] Bad protocol option.
	10043 [10043] Protocol not supported.
	10044 [10044] Socket type not supported.
	10045 [10045] Operation not supported on socket.
	10046 [10046] Protocol family not supported.
	10047 [10047] Address family not supported by protocol family.
	10048 [10048] Address already in use.
	10049 [10049] Can't assign requested address.
	10050 [10050] Network is down.
	10051 [10051] Network is unreachable.
	10052 [10052] Net dropped connection or reset.
	10053 [10053] Software caused connection abort.
	10054 [10054] Connection reset by peer.
	10055 [10055] No buffer space available.
	10056 [10056] Socket is already connected.
	10057 [10057] Socket is not connected.
	10058 [10058] Can't send after socket shutdown.
	10059 [10059] Too many references, can't splice.
	10060 [10060] Connection timed out.
	10061 [10061] Connection refused.
	10062 [10062] Too many levels of symbolic links.
	10063 [10063] File name too long.
	10064 [10064] Host is down.
	10065 [10065] No route to host.
	10066 [10066] Directory not empty
	10067 [10067] Too many processes.
	10068 [10068] Too many users.
	10069 [10069] Disc Quota Exceeded.
	10070 [10070] Stale NFS file handle.
	10071 [10071] Too many levels of remote in path.
	10091 [10091] Network subsystem is unavailable.
	10092 [10092] WINSOCK DLL Version out of range.
	10093 [10093] Winsock not loaded yet.
	11001 [11001] Host not found.
	11002 [11002] Non-authoritative 'Host not found' (try again or check DNS setup).
	11003 [11003] Non-recoverable errors: FORMERR, REFUSED, NOTIMP.
	11004 [11004] Valid name, no data record (check DNS setup).