PipeExec Class

Properties   Methods   Events   Config Settings   Errors  

PipeExec provides an easy way to start and interact with a process over Stdin, Stdout, and Stderr.

Syntax

PipeExec

Remarks

The PipeExec component provides a way to launch a process and then send/receive data to/from the process. To begin set ProcessFileName to the path of the process on disk. Optionally set ProcessArgs and ProcessWorkingDir.

Call StartProcess to start the process. Next call Send to send data to the process. Received data will be provided through the Stdout and Stderr events.

To terminate the process call StopProcess.

Example Code Pipeexec exec = new Pipeexec(); exec.OnStdout += exec_OnStdout; exec.ProcessFileName = @"C:\Windows\system32\cmd.exe"; exec.ProcessArgs = "/Q"; exec.StartProcess(); exec.Stdin = "dir" + System.Environment.NewLine; while (true) //Wait for output exec.DoEvents(); static void exec_OnStdout(object sender, PipeexecStdoutEventArgs e) { Console.WriteLine(e.Text); }

Property List

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

Method List

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

Event List

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

Config Settings

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

AcceptData Property (PipeExec Class)

Enables or disables data reception (the Stdout and Stderr events).

Syntax

• C++
• C
• Qt

ANSI (Cross Platform)
int GetAcceptData();
int SetAcceptData(int bAcceptData);

Unicode (Windows)
BOOL GetAcceptData();
INT SetAcceptData(BOOL bAcceptData);

int ipworksipc_pipeexec_getacceptdata(void* lpObj);
int ipworksipc_pipeexec_setacceptdata(void* lpObj, int bAcceptData);

bool GetAcceptData();
int SetAcceptData(bool bAcceptData);

Default Value

TRUE

Remarks

This property enables or disables data reception (the Stdout and Stderr events). Setting this property to False, temporarily disables data reception. Setting this property to True, re-enables data reception.

This property is not available at design time.

Data Type

Boolean

BytesSent Property (PipeExec Class)

The number of bytes actually sent after a call to the SendStdinText or SendStdinBytes method.

Syntax

• C++
• C
• Qt

ANSI (Cross Platform)
int GetBytesSent();

Unicode (Windows)
INT GetBytesSent();

int ipworksipc_pipeexec_getbytessent(void* lpObj);

int GetBytesSent();

Default Value

0

Remarks

This property indicates how many bytes were sent after the last call to SendStdinText or SendStdinBytes. Please check the SendStdinText or SendStdinBytes method for more information. Note: that BytesSent will always return 0 when the component is operating in synchronous mode (i.e., the Timeout property is set to a positive value.)

This property is read-only and not available at design time.

Data Type

Integer

EOL Property (PipeExec Class)

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

Syntax

• C++
• C
• Qt

ANSI (Cross Platform)
int GetEOL(char* &lpEOL, int &lenEOL);
int SetEOL(const char* lpEOL, int lenEOL);

Unicode (Windows)
INT GetEOL(LPSTR &lpEOL, INT &lenEOL);
INT SetEOL(LPCSTR lpEOL, INT lenEOL);

int ipworksipc_pipeexec_geteol(void* lpObj, char** lpEOL, int* lenEOL);
int ipworksipc_pipeexec_seteol(void* lpObj, const char* lpEOL, int lenEOL);

QByteArray GetEOL();
int SetEOL(QByteArray qbaEOL);

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 CRLF ("\r\n") 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 CRLF ("\r\n") 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.

Data Type

Binary String

ProcessArgs Property (PipeExec Class)

The arguments to pass to the process.

Syntax

• C++
• C
• Qt

ANSI (Cross Platform)
char* GetProcessArgs();
int SetProcessArgs(const char* lpszProcessArgs);

Unicode (Windows)
LPWSTR GetProcessArgs();
INT SetProcessArgs(LPCWSTR lpszProcessArgs);

char* ipworksipc_pipeexec_getprocessargs(void* lpObj);
int ipworksipc_pipeexec_setprocessargs(void* lpObj, const char* lpszProcessArgs);

QString GetProcessArgs();
int SetProcessArgs(QString qsProcessArgs);

Default Value

""

Remarks

This property specifies the arguments that will be passed to the process when it is started.

This property is not available at design time.

Data Type

String

ProcessFileName Property (PipeExec Class)

The path to the file on disk to execute.

Syntax

• C++
• C
• Qt

ANSI (Cross Platform)
char* GetProcessFileName();
int SetProcessFileName(const char* lpszProcessFileName);

Unicode (Windows)
LPWSTR GetProcessFileName();
INT SetProcessFileName(LPCWSTR lpszProcessFileName);

char* ipworksipc_pipeexec_getprocessfilename(void* lpObj);
int ipworksipc_pipeexec_setprocessfilename(void* lpObj, const char* lpszProcessFileName);

QString GetProcessFileName();
int SetProcessFileName(QString qsProcessFileName);

Default Value

""

Remarks

This property specifies the path to the file on disk that will be executed. ProcessArgs optionally specifies the arguments that will be passed. ProcessWorkingDir optionally specifies the working directory in which the process will run.

This property is not available at design time.

Data Type

String

ProcessRunning Property (PipeExec Class)

Whether the process is running.

Syntax

• C++
• C
• Qt

ANSI (Cross Platform)
int GetProcessRunning();

Unicode (Windows)
BOOL GetProcessRunning();

int ipworksipc_pipeexec_getprocessrunning(void* lpObj);

bool GetProcessRunning();

Default Value

FALSE

Remarks

This property indicates whether the process specified by ProcessFileName is running.

After calling StartProcess this property returns True. After calling StopProcess this property returns False.

This property is read-only and not available at design time.

Data Type

Boolean

ProcessWorkingDir Property (PipeExec Class)

The working directory of the process.

Syntax

• C++
• C
• Qt

ANSI (Cross Platform)
char* GetProcessWorkingDir();
int SetProcessWorkingDir(const char* lpszProcessWorkingDir);

Unicode (Windows)
LPWSTR GetProcessWorkingDir();
INT SetProcessWorkingDir(LPCWSTR lpszProcessWorkingDir);

char* ipworksipc_pipeexec_getprocessworkingdir(void* lpObj);
int ipworksipc_pipeexec_setprocessworkingdir(void* lpObj, const char* lpszProcessWorkingDir);

QString GetProcessWorkingDir();
int SetProcessWorkingDir(QString qsProcessWorkingDir);

Default Value

""

Remarks

This property optionally specifies the working directory in which the process will run.

This property is not available at design time.

Data Type

String

SingleLineMode Property (PipeExec Class)

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

Syntax

• C++
• C
• Qt

ANSI (Cross Platform)
int GetSingleLineMode();
int SetSingleLineMode(int bSingleLineMode);

Unicode (Windows)
BOOL GetSingleLineMode();
INT SetSingleLineMode(BOOL bSingleLineMode);

int ipworksipc_pipeexec_getsinglelinemode(void* lpObj);
int ipworksipc_pipeexec_setsinglelinemode(void* lpObj, int bSingleLineMode);

bool GetSingleLineMode();
int SetSingleLineMode(bool bSingleLineMode);

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.

This property is not available at design time.

Data Type

Boolean

Timeout Property (PipeExec Class)

This property includes the timeout for the class.

Syntax

• C++
• C
• Qt

ANSI (Cross Platform)
int GetTimeout();
int SetTimeout(int iTimeout);

Unicode (Windows)
INT GetTimeout();
INT SetTimeout(INT iTimeout);

int ipworksipc_pipeexec_gettimeout(void* lpObj);
int ipworksipc_pipeexec_settimeout(void* lpObj, int iTimeout);

int GetTimeout();
int SetTimeout(int iTimeout);

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 fails with an error.

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.

Data Type

Integer

Config Method (PipeExec Class)

Sets or retrieves a configuration setting.

Syntax

• C++
• C
• Qt

ANSI (Cross Platform)
char* Config(const char* lpszConfigurationString);

Unicode (Windows)
LPWSTR Config(LPCWSTR lpszConfigurationString);

char* ipworksipc_pipeexec_config(void* lpObj, const char* lpszConfigurationString);

QString Config(const QString& qsConfigurationString);

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.

Error Handling (C++)

This method returns a String value; after it returns, call the GetLastErrorCode() method to obtain its result code; 0 indicates success, while a non-zero error code indicates that this method encountered an error during its execution. If an error occurs, the GetLastError() method can be called to retrieve the associated error message.

DoEvents Method (PipeExec Class)

This method processes events from the internal message queue.

Syntax

• C++
• C
• Qt

ANSI (Cross Platform)
int DoEvents();

Unicode (Windows)
INT DoEvents();

int ipworksipc_pipeexec_doevents(void* lpObj);

int 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.

Error Handling (C++)

This method returns a result code; 0 indicates success, while a non-zero error code indicates that this method encountered an error during its execution. If an error occurs, the GetLastError() method can be called to retrieve the associated error message. (Note: This method's result code can also be obtained by calling the GetLastErrorCode() method after it returns.)

GetLine Method (PipeExec Class)

This method gets a line of text from the server.

Syntax

• C++
• C
• Qt

ANSI (Cross Platform)
char* GetLine();

Unicode (Windows)
LPWSTR GetLine();

char* ipworksipc_pipeexec_getline(void* lpObj);

QString 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.

Error Handling (C++)

This method returns a String value; after it returns, call the GetLastErrorCode() method to obtain its result code; 0 indicates success, while a non-zero error code indicates that this method encountered an error during its execution. If an error occurs, the GetLastError() method can be called to retrieve the associated error message.

Interrupt Method (PipeExec Class)

This method interrupts the current action.

Syntax

• C++
• C
• Qt

ANSI (Cross Platform)
int Interrupt();

Unicode (Windows)
INT Interrupt();

int ipworksipc_pipeexec_interrupt(void* lpObj);

int 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.

Error Handling (C++)

This method returns a result code; 0 indicates success, while a non-zero error code indicates that this method encountered an error during its execution. If an error occurs, the GetLastError() method can be called to retrieve the associated error message. (Note: This method's result code can also be obtained by calling the GetLastErrorCode() method after it returns.)

Send Method (PipeExec Class)

Sends data over the connected pipe.

Syntax

• C++
• C
• Qt

ANSI (Cross Platform)
int Send(const char* lpText, int lenText);

Unicode (Windows)
INT Send(LPCSTR lpText, INT lenText);

int ipworksipc_pipeexec_send(void* lpObj, const char* lpText, int lenText);

int Send(QByteArray qbaText);

Remarks

This method sends data to the server.

Error Handling (C++)

This method returns a result code; 0 indicates success, while a non-zero error code indicates that this method encountered an error during its execution. If an error occurs, the GetLastError() method can be called to retrieve the associated error message. (Note: This method's result code can also be obtained by calling the GetLastErrorCode() method after it returns.)

SendFile Method (PipeExec Class)

Sends the file over the connected pipe.

Syntax

• C++
• C
• Qt

ANSI (Cross Platform)
int SendFile(const char* lpszFileName);

Unicode (Windows)
INT SendFile(LPCWSTR lpszFileName);

int ipworksipc_pipeexec_sendfile(void* lpObj, const char* lpszFileName);

int SendFile(const QString& qsFileName);

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.

Error Handling (C++)

This method returns a result code; 0 indicates success, while a non-zero error code indicates that this method encountered an error during its execution. If an error occurs, the GetLastError() method can be called to retrieve the associated error message. (Note: This method's result code can also be obtained by calling the GetLastErrorCode() method after it returns.)

SendLine Method (PipeExec Class)

This method sends a string followed by a newline.

Syntax

• C++
• C
• Qt

ANSI (Cross Platform)
int SendLine(const char* lpszText);

Unicode (Windows)
INT SendLine(LPCWSTR lpszText);

int ipworksipc_pipeexec_sendline(void* lpObj, const char* lpszText);

int SendLine(const QString& qsText);

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 CRLF ("\r\n") .

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

Error Handling (C++)

This method returns a result code; 0 indicates success, while a non-zero error code indicates that this method encountered an error during its execution. If an error occurs, the GetLastError() method can be called to retrieve the associated error message. (Note: This method's result code can also be obtained by calling the GetLastErrorCode() method after it returns.)

SendStdinBytes Method (PipeExec Class)

This method sends binary data over the connected pipe.

Syntax

• C++
• C
• Qt

ANSI (Cross Platform)
int SendStdinBytes(const char* lpData, int lenData);

Unicode (Windows)
INT SendStdinBytes(LPCSTR lpData, INT lenData);

int ipworksipc_pipeexec_sendstdinbytes(void* lpObj, const char* lpData, int lenData);

int SendStdinBytes(QByteArray qbaData);

Remarks

This method sends the specified binary data to the server over Stdin. To send text, use the SendStdinText 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 fails with error 10035: "[10035] Operation would block" (WSAEWOULDBLOCK). You can check this error, and then try to send the data again. 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).

Error Handling (C++)

This method returns a result code; 0 indicates success, while a non-zero error code indicates that this method encountered an error during its execution. If an error occurs, the GetLastError() method can be called to retrieve the associated error message. (Note: This method's result code can also be obtained by calling the GetLastErrorCode() method after it returns.)

SendStdinText Method (PipeExec Class)

This method sends text over the connected pipe.

Syntax

• C++
• C
• Qt

ANSI (Cross Platform)
int SendStdinText(const char* lpszText);

Unicode (Windows)
INT SendStdinText(LPCWSTR lpszText);

int ipworksipc_pipeexec_sendstdintext(void* lpObj, const char* lpszText);

int SendStdinText(const QString& qsText);

Remarks

This method sends the specified text to the server over Stdin. To send binary data, use the SendStdinBytes 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 fails with error 10035: "[10035] Operation would block" (WSAEWOULDBLOCK). You can check this error, and then try to send the data again. 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).

Error Handling (C++)

This method returns a result code; 0 indicates success, while a non-zero error code indicates that this method encountered an error during its execution. If an error occurs, the GetLastError() method can be called to retrieve the associated error message. (Note: This method's result code can also be obtained by calling the GetLastErrorCode() method after it returns.)

StartProcess Method (PipeExec Class)

Starts the process.

Syntax

• C++
• C
• Qt

ANSI (Cross Platform)
int StartProcess();

Unicode (Windows)
INT StartProcess();

int ipworksipc_pipeexec_startprocess(void* lpObj);

int StartProcess();

Remarks

This method starts the process specified by StartProcess. After starting the process data may be sent to the process by calling Send, SendLine, Send.

Data received from the process will be available from the Stdout and Stderr events.

The following properties are applicable when calling this method:

• ProcessFileName (required)
• ProcessArgs
• ProcessWorkingDir

Error Handling (C++)

This method returns a result code; 0 indicates success, while a non-zero error code indicates that this method encountered an error during its execution. If an error occurs, the GetLastError() method can be called to retrieve the associated error message. (Note: This method's result code can also be obtained by calling the GetLastErrorCode() method after it returns.)

StopProcess Method (PipeExec Class)

Stops the process.

Syntax

• C++
• C
• Qt

ANSI (Cross Platform)
int StopProcess();

Unicode (Windows)
INT StopProcess();

int ipworksipc_pipeexec_stopprocess(void* lpObj);

int StopProcess();

Remarks

This method stops the process.

Error Handling (C++)

This method returns a result code; 0 indicates success, while a non-zero error code indicates that this method encountered an error during its execution. If an error occurs, the GetLastError() method can be called to retrieve the associated error message. (Note: This method's result code can also be obtained by calling the GetLastErrorCode() method after it returns.)

Error Event (PipeExec Class)

Fired when information is available about errors during data delivery.

Syntax

• C++
• C
• Qt

ANSI (Cross Platform)
virtual int FireError(PipeExecErrorEventParams *e);

typedef struct {
  int ErrorCode;
  const char *Description;
  int reserved;
} PipeExecErrorEventParams;


Unicode (Windows)
virtual INT FireError(PipeExecErrorEventParams *e);

typedef struct {
  INT ErrorCode;
  LPCWSTR Description;
  INT reserved;
} PipeExecErrorEventParams;

#define EID_PIPEEXEC_ERROR 1

virtual INT IPWORKSIPC_CALL FireError(INT &iErrorCode, LPSTR &lpszDescription);

class PipeExecErrorEventParams {
public:
  int ErrorCode();

  const QString &Description();

  int EventRetVal();
  void SetEventRetVal(int iRetVal);
};

// To handle, connect one or more slots to this signal.
void Error(PipeExecErrorEventParams *e);

// Or, subclass PipeExec and override this emitter function.
virtual int FireError(PipeExecErrorEventParams *e) {...}

Remarks

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

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 (PipeExec Class)

Fired when the class is ready to send data.

Syntax

• C++
• C
• Qt

ANSI (Cross Platform)
virtual int FireReadyToSend(PipeExecReadyToSendEventParams *e);

typedef struct {
  int reserved;
} PipeExecReadyToSendEventParams;


Unicode (Windows)
virtual INT FireReadyToSend(PipeExecReadyToSendEventParams *e);

typedef struct {
  INT reserved;
} PipeExecReadyToSendEventParams;

#define EID_PIPEEXEC_READYTOSEND 2

virtual INT IPWORKSIPC_CALL FireReadyToSend();

class PipeExecReadyToSendEventParams {
public:
  int EventRetVal();
  void SetEventRetVal(int iRetVal);
};

// To handle, connect one or more slots to this signal.
void ReadyToSend(PipeExecReadyToSendEventParams *e);

// Or, subclass PipeExec and override this emitter function.
virtual int FireReadyToSend(PipeExecReadyToSendEventParams *e) {...}

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.

Stderr Event (PipeExec Class)

Fired when data come in through stderr.

Syntax

• C++
• C
• Qt

ANSI (Cross Platform)
virtual int FireStderr(PipeExecStderrEventParams *e);

typedef struct {
  const char *Text;
  int lenText;
  int EOL;
  int reserved;
} PipeExecStderrEventParams;


Unicode (Windows)
virtual INT FireStderr(PipeExecStderrEventParams *e);

typedef struct {
  LPCSTR Text;
  INT lenText;
  BOOL EOL;
  INT reserved;
} PipeExecStderrEventParams;

#define EID_PIPEEXEC_STDERR 3

virtual INT IPWORKSIPC_CALL FireStderr(LPSTR &lpText, INT &lenText, BOOL &bEOL);

class PipeExecStderrEventParams {
public:
  const QByteArray &Text();

  bool EOL();

  int EventRetVal();
  void SetEventRetVal(int iRetVal);
};

// To handle, connect one or more slots to this signal.
void Stderr(PipeExecStderrEventParams *e);

// Or, subclass PipeExec and override this emitter function.
virtual int FireStderr(PipeExecStderrEventParams *e) {...}

Remarks

The Stderr event is fired every time the process outputs a line in its standard output. The incoming data is provided through the Text parameter.

Stdout Event (PipeExec Class)

Fired when data come in through stdout.

Syntax

• C++
• C
• Qt

ANSI (Cross Platform)
virtual int FireStdout(PipeExecStdoutEventParams *e);

typedef struct {
  const char *Text;
  int lenText;
  int EOL;
  int reserved;
} PipeExecStdoutEventParams;


Unicode (Windows)
virtual INT FireStdout(PipeExecStdoutEventParams *e);

typedef struct {
  LPCSTR Text;
  INT lenText;
  BOOL EOL;
  INT reserved;
} PipeExecStdoutEventParams;

#define EID_PIPEEXEC_STDOUT 4

virtual INT IPWORKSIPC_CALL FireStdout(LPSTR &lpText, INT &lenText, BOOL &bEOL);

class PipeExecStdoutEventParams {
public:
  const QByteArray &Text();

  bool EOL();

  int EventRetVal();
  void SetEventRetVal(int iRetVal);
};

// To handle, connect one or more slots to this signal.
void Stdout(PipeExecStdoutEventParams *e);

// Or, subclass PipeExec and override this emitter function.
virtual int FireStdout(PipeExecStdoutEventParams *e) {...}

Remarks

The Stdout event is fired every time the process outputs a line in its standard output. The incoming data is 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).

Config Settings (PipeExec Class)

PipeExec Config Settings

Base Config Settings

Trappable Errors (PipeExec Class)

Error Handling (C++)

Call the GetLastErrorCode() method to obtain the last called method's result code; 0 indicates success, while a non-zero error code indicates that this method encountered an error during its execution. Known error codes are listed below. If an error occurs, the GetLastError() method can be called to retrieve the associated error message.

PipeExec Errors