PipeClient Module

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The PipeClient module is a simple client for connecting and communicating over named pipes.

Syntax

IPWorksIPC.PipeClient

Remarks

The PipeClient class is used to connect to an existing pipe server. After connecting the transfer of data is handled very similarly to socket communication.

To begin, first set PipeName to the name of the pipe to which the connection will be made. Call Connect or set Connected to True to establish the connection. The Connected event will fire when the connection is complete.

After connecting call Send or SendFile to send data. Incoming data is received through the DataIn event.

To disconnect call Disconnect or set Connected to False.

Synchronous and Asynchronous Operation

If the Timeout property is set to 0, the class will behave asynchronously and all operations return immediately, potentially failing with an error if they can't be completed immediately.

If Timeout is set to a positive value, the class will behave synchronously and wait for the operation to complete before returning control.

The class 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 class .

Note: By default, all timeouts are inactivity timeouts, that is, 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.

Property List

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

Method List

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

Event List

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

Config Settings

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

AcceptData Property (PipeClient Module)

This property indicates whether data reception is currently enabled.

Syntax

• Swift
• Objective-C

public var acceptData: Bool {
  get {...}
}

@property (nonatomic,readonly,assign,getter=acceptData) BOOL acceptData;

- (BOOL)acceptData;

Default Value

True

Remarks

This property indicates whether data reception is currently enabled. When , data reception is disabled and the DataIn event will not fire. Use the PauseData and ProcessData methods to pause and resume data reception.

This property is read-only.

BytesSent Property (PipeClient Module)

This property includes the number of bytes actually sent after a call to the SendBytes method.

Syntax

• Swift
• Objective-C

public var bytesSent: Int32 {
  get {...}
}

@property (nonatomic,readonly,assign,getter=bytesSent) int bytesSent;

- (int)bytesSent;

Default Value

0

Remarks

This property indicates how many bytes were sent after the last call to SendBytes. Please check the SendBytes method for more information.

Note: that BytesSent will always return 0 when the class is operating in synchronous mode (i.e., the Timeout property is set to a positive value.)

This property is read-only.

Connected Property (PipeClient Module)

Triggers a connection or disconnection.

Syntax

• Swift
• Objective-C

public var connected: Bool {
  get {...}
  set {...}
}

@property (nonatomic,readwrite,assign,getter=connected,setter=setConnected:) BOOL connected;

- (BOOL)connected;
- (void)setConnected :(BOOL)newConnected;

Default Value

False

Remarks

This property indicates whether the class is connected to the remote host. Use the Connect and Disconnect methods to manage the connection.

This property triggers a connection or disconnection. Setting this property to True makes the class attempt to connect to the pipe identified by the PipeName property. If successful, after the connection is achieved the value of the property changes to True and the Connected event is fired.

Setting this property to False closes the connection.

EOL Property (PipeClient Module)

This property is used to break the incoming data stream into chunks separated by EOL .

Syntax

• Swift
• Objective-C

public var eol: String {
  get {...}
  set {...}
}

public var eolB: Data {
  get {...}
  set {...}
}

@property (nonatomic,readwrite,assign,getter=EOL,setter=setEOL:) NSString* EOL;

- (NSString*)EOL;
- (void)setEOL :(NSString*)newEOL;

@property (nonatomic,readwrite,assign,getter=EOLB,setter=setEOLB:) NSData* EOLB;

- (NSData*)EOLB;
- (void)setEOLB :(NSData*)newEOL;

Default Value

""

Remarks

This property is used to define boundaries in the input stream using the value of the property.

This property is especially useful with ASCII files. Setting it to enables the incoming ASCII text stream to split into defined lines. In this case, one event is fired for each line received (as well as in packet boundaries). The bytes are discarded.

This property is a binary string. Notably, this means that it can be more than one byte long, and it can contain NULL bytes.

PipeName Property (PipeClient Module)

The name of the pipe.

Syntax

• Swift
• Objective-C

public var pipeName: String {
  get {...}
  set {...}
}

@property (nonatomic,readwrite,assign,getter=pipeName,setter=setPipeName:) NSString* pipeName;

- (NSString*)pipeName;
- (void)setPipeName :(NSString*)newPipeName;

Default Value

""

Remarks

This property specifies the name of the pipe.

This may be the name by itself, for instance "MyPipe", or in the format "\\.\pipe\MyPipe".

RecordLength Property (PipeClient Module)

The length of received data records.

Syntax

• Swift
• Objective-C

public var recordLength: Int32 {
  get {...}
  set {...}
}

@property (nonatomic,readwrite,assign,getter=recordLength,setter=setRecordLength:) int recordLength;

- (int)recordLength;
- (void)setRecordLength :(int)newRecordLength;

Default Value

0

Remarks

If set to a positive value, this property defines the length of data records to be received. The class will accumulate data until RecordLength is reached and only then fire the DataIn event with data of length RecordLength. This allows data to be received as records of known length. This value can be changed at any time, including within the DataIn event.

The default value is 0, meaning this property is not used.

SingleLineMode Property (PipeClient Module)

This property includes a special mode for line-oriented protocols.

Syntax

• Swift
• Objective-C

public var singleLineMode: Bool {
  get {...}
  set {...}
}

@property (nonatomic,readwrite,assign,getter=singleLineMode,setter=setSingleLineMode:) BOOL singleLineMode;

- (BOOL)singleLineMode;
- (void)setSingleLineMode :(BOOL)newSingleLineMode;

Default Value

False

Remarks

When this property is set to True, the class treats the incoming data stream as lines separated by carriage return line feed (CRLF), CR, or LF. The EOL property is ignored.

When this property is set to True, AcceptData automatically will be set to False. Please refer to the GetLine method for more information.

Timeout Property (PipeClient Module)

This property includes the timeout for the module.

Syntax

• Swift
• Objective-C

public var timeout: Int32 {
  get {...}
  set {...}
}

@property (nonatomic,readwrite,assign,getter=timeout,setter=setTimeout:) int timeout;

- (int)timeout;
- (void)setTimeout :(int)newTimeout;

Default Value

60

Remarks

If the Timeout property is set to 0, all operations return immediately, potentially failing with a WOULDBLOCK error if data cannot be sent immediately.

If Timeout is set to a positive value, data is sent in a blocking manner and the class will wait for the operation to complete before returning control. The class will handle any potential WOULDBLOCK errors internally and automatically retry the operation for a maximum of Timeout seconds.

The class 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 class .

Note: By default, all timeouts are inactivity timeouts, that is, 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 (PipeClient Module)

Sets or retrieves a configuration setting.

Syntax

• Swift
• Objective-C

public func config(configurationString: String) throws -> String

- (NSString*)config:(NSString*)configurationString;

Remarks

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

These settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the class, 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.

Connect Method (PipeClient Module)

Connects to a named pipe.

Syntax

• Swift
• Objective-C

public func connect() throws -> Void

- (void)connect;

Remarks

This method connects to a named pipe specified by PipeName. Calling this method is equivalent to setting the Connected property to True.

Example (Connecting)

PipeClient.PipeName = "MyPipe"; PipeClient.Connect();

Disconnect Method (PipeClient Module)

Disconnects from the named pipe.

Syntax

• Swift
• Objective-C

public func disconnect() throws -> Void

- (void)disconnect;

Remarks

This method disconnects from the pipe. Calling this method is equivalent to setting the Connected property to False.

DoEvents Method (PipeClient Module)

This method processes events from the internal message queue.

Syntax

• Swift
• Objective-C

public func doEvents() throws -> Void

- (void)doEvents;

Remarks

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

GetLine Method (PipeClient Module)

This method gets a line of text from the server.

Syntax

• Swift
• Objective-C

public func getLine() throws -> String

- (NSString*)getLine;

Remarks

This method gets a line of text from the server. This method is an alternative method of receiving data for line-oriented protocols. The class will block if necessary and then will return the received line. AcceptData will be set automatically to True when the method is called, and then will be set to False after a line is received.

Please refer to the SingleLineMode property for more information.

Interrupt Method (PipeClient Module)

This method interrupts the current action.

Syntax

• Swift
• Objective-C

public func interrupt() throws -> Void

- (void)interrupt;

Remarks

This method interrupts the current action. If you use SendFile to upload a file, the class will run synchronously until the upload is completed. This method will allow you to stop the file from uploading without disconnecting from the host.

ProcessData Method (PipeClient Module)

This method reenables data reception after a call to PauseData .

Syntax

• Swift
• Objective-C

public func processData() throws -> Void

- (void)processData;

Remarks

This method reenables data reception after a previous call to PauseData. When PauseData is called, the DataIn event will not fire. To reenable data reception and allow DataIn to fire, call this method.

Note: This method is used only after previously calling PauseData. It does not need to be called to process incoming data by default.

Send Method (PipeClient Module)

Sends data over the connected pipe.

Syntax

• Swift
• Objective-C

public func send(text: Data) throws -> Void

- (void)send:(NSData*)text;

Remarks

This method sends data to the server.

SendBytes Method (PipeClient Module)

This method sends binary data over the connected pipe.

Syntax

• Swift
• Objective-C

public func sendBytes(data: Data) throws -> Void

- (void)sendBytes:(NSData*)data;

Remarks

This method sends the specified binary data to the server. To send text, use the SendText method instead.

When Timeout is set to 0 the class will behave asynchronously. If you are sending data to the receiving process faster than it can process it, the outgoing queue might fill up. When this happens, the class The BytesSent property shows how many bytes were sent (if any). If 0 bytes were sent, then you can wait for the ReadyToSend event before attempting to send data again. (However, please note that ReadyToSend is not fired when part of the data is successfully sent).

SendFile Method (PipeClient Module)

Sends the file over the connected pipe.

Syntax

• Swift
• Objective-C

public func sendFile(fileName: String) throws -> Void

- (void)sendFile:(NSString*)fileName;

Remarks

This method sends the specified file to the server/process over the connected pipe.

Timeout must be set to a positive value so that the class will operate synchronously.

SendLine Method (PipeClient Module)

This method sends a string followed by a newline.

Syntax

• Swift
• Objective-C

public func sendLine(text: String) throws -> Void

- (void)sendLine:(NSString*)text;

Remarks

This method sends a string followed by a newline. This method is used to send data with line-oriented protocols. The line is followed by .

Please refer to the GetLine method and SingleLineMode property for more information.

SendText Method (PipeClient Module)

This method sends text over the connected pipe.

Syntax

• Swift
• Objective-C

public func sendText(text: String) throws -> Void

- (void)sendText:(NSString*)text;

Remarks

This method sends the specified text to the server. To send binary data, use the SendBytes method instead.

When Timeout is set to 0 the class will behave asynchronously. If you are sending data to the receiving process faster than it can process it, the outgoing queue might fill up. When this happens, the class The BytesSent property shows how many bytes were sent (if any). If 0 bytes were sent, then you can wait for the ReadyToSend event before attempting to send data again. (However, please note that ReadyToSend is not fired when part of the data is successfully sent).

Connected Event (PipeClient Module)

Fired immediately after a connection completes.

Syntax

• Swift
• Objective-C

func onConnected()

- (void)onConnected;

Remarks

When the connection is successfully established this event will fire.

DataIn Event (PipeClient Module)

This event is fired when data (complete lines) come in.

Syntax

• Swift
• Objective-C

func onDataIn(text: Data, eol: Bool)

- (void)onDataIn:(NSData*)text :(BOOL)EOL;

Remarks

Trapping the DataIn event is your only chance to get the data coming from the other end of the connection. The incoming data are provided through the Text parameter.

EOL indicates whether or not the EOL string was found at the end of Text. If the EOL string was found, then EOL is True.

If Text is part of a data portion of length larger than MaxLineLength with no EOL strings in it, then EOL is False. Note: This means that one or more DataIn events with EOL set to False can be received during a connection.

If the EOL property is "" (empty string), then EOL can be disregarded (it is always True).

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.

Disconnected Event (PipeClient Module)

Fired when a connection is closed.

Syntax

• Swift
• Objective-C

func onDisconnected()

- (void)onDisconnected;

Remarks

When the connection is closed this event will fire.

Error Event (PipeClient Module)

Fired when information is available about errors during data delivery.

Syntax

• Swift
• Objective-C

func onError(errorCode: Int32, description: String)

- (void)onError:(int)errorCode :(NSString*)description;

Remarks

The Error event is fired in case of exceptional conditions during message processing. Normally the class .

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.

ReadyToSend Event (PipeClient Module)

Fired when the component is ready to send data.

Syntax

• Swift
• Objective-C

func onReadyToSend()

- (void)onReadyToSend;

Remarks

The ReadyToSend event indicates that the underlying pipe is ready to accept data again after a failed send. The event is also fired immediately after a connection to the remote host is established.

Config Settings (PipeClient Module)

PipeClient Config Settings

Base Config Settings

Trappable Errors (PipeClient Module)

PipeClient Errors