IPWorks 2022 C++ Edition
Version 22.0 [Build 8369]

ICMP Class

Properties   Methods   Events   Config Settings   Errors  

The ICMP class is used to facilitate ICMP communications. It can act both as a client and a server and can communicate with any number of hosts simultaneously. It also can generate and receive broadcast packets.

Syntax

ICMP

Remarks

The interface of the class is similar to the interface of TCPClient, only it is much simpler. The class is activated/deactivated by using the Active property. This property enables or disables the sending or receiving of data. Data can be sent in the same way as TCPClient, using the Send method and Text parameter or the DataToSend property. The destination is specified using the RemoteHost property. The class automatically creates an ICMP header containing MessageType, MessageSubType, and a checksum for the message.

If the UseConnection configuration setting is set to True, then a local association is created with the remote host. Otherwise, the class can receive datagrams (packets) from any host and can send datagrams to any host. Packets can be broadcast on the local net by setting the destination to 255.255.255.255.

Inbound data is received through the DataIn event.

The operation of the class is almost completely asynchronous. All the calls, except the ones that deal with domain name resolution, operate through Windows messages (no blocking calls). The gain in performance is considerable when compared with using blocking calls.

Property List


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

AcceptDataThis property enables or disables data reception (the DataIn event).
ActiveThis property indicates whether the class is active.
DontRouteIf this property is set to True, it forces the socket to send data directly to the interface (no routing).
LocalHostThe name of the local host or user-assigned IP interface through which connections are initiated or accepted.
MessageSubTypeThis property is the subtype of the ICMP message (part of the ICMP header).
MessageTypeThis property includes the type of the ICMP message (part of the ICMP header).
RemoteHostThis property includes the address of the RemoteHost. Domain names are resolved to IP addresses.
TimeoutA timeout for the class.
TimeToLiveThis property includes the time-to-live (TTL) value for the ICMP packets sent by the class.

Method List


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

ActivateThis method enables sending and receiving of data.
ConfigSets or retrieves a configuration setting.
DeactivateThis method disables sending and receiving of data.
DoEventsProcesses events from the internal message queue.
PauseDataThis method pauses data reception.
ProcessDataThis method reenables data reception after a call to PauseData .
ResetReset the class.
ResolveRemoteHostResolves the hostname in RemoteHost to an IP address.
SendThis method sends data to the remote host.
SendBytesThis method sends data to the remote host.
SendTextThis method sends data to the remote host.

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.

DataInThis event is fired when a new ICMP messages come in.
ErrorInformation about errors during data delivery.
ReadyToSendFired when the class is ready to send data.

Config Settings


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

DelayHostResolutionWhether the hostname is resolved when RemoteHost is set.
DontFragmentWhether the DontFragment control flag is set.
IcmpDllTimeoutThe timeout for the class when using the icmp.dll.
MaxMessageSizeThe maximum length of the messages that can be received.
MulticastTTLThe time to live (TTL) value for multicast ICMP packets sent by the class.
ReceiveAllModeEnables a socket to receive all IPv4 or IPv6 packets on the network.
TimeoutInMillisecondsThe timeout is treated as milliseconds.
UseConnectionDetermines whether to use a connected socket.
UseICMPDLLUse the icmp.dll included on Windows Systems.
UseIPHLPDLLUse the iphlpapi.dll included on Windows Systems.
UseIPv6Whether to use IPv6.
AbsoluteTimeoutDetermines whether timeouts are inactivity timeouts or absolute timeouts.
FirewallDataUsed to send extra data to the firewall.
InBufferSizeThe size in bytes of the incoming queue of the socket.
OutBufferSizeThe size in bytes of the outgoing queue of the socket.
BuildInfoInformation about the product's build.
CodePageThe system code page used for Unicode to Multibyte translations.
LicenseInfoInformation about the current license.
ProcessIdleEventsWhether the class uses its internal event loop to process events when the main thread is idle.
SelectWaitMillisThe length of time in milliseconds the class will wait when DoEvents is called if there are no events to process.
UseInternalSecurityAPITells the class whether or not to use the system security libraries or an internal implementation.

AcceptData Property (ICMP Class)

This property enables or disables data reception (the DataIn event).

Syntax

ANSI (Cross Platform)
int GetAcceptData();
int SetAcceptData(int bAcceptData); Unicode (Windows) BOOL GetAcceptData();
INT SetAcceptData(BOOL bAcceptData);
int ipworks_icmp_getacceptdata(void* lpObj);
int ipworks_icmp_setacceptdata(void* lpObj, int bAcceptData);
bool GetAcceptData();
int SetAcceptData(bool bAcceptData);

Default Value

TRUE

Remarks

This property enables or disables data reception (the DataIn event). Setting this property to False, temporarily disables data reception (and the DataIn event). Setting this property to True, reenables data reception.

Note: It is recommended to use the PauseData or ProcessData method instead of setting this property.

This property is not available at design time.

Data Type

Boolean

Active Property (ICMP Class)

This property indicates whether the class is active.

Syntax

ANSI (Cross Platform)
int GetActive();
int SetActive(int bActive); Unicode (Windows) BOOL GetActive();
INT SetActive(BOOL bActive);
int ipworks_icmp_getactive(void* lpObj);
int ipworks_icmp_setactive(void* lpObj, int bActive);
bool GetActive();
int SetActive(bool bActive);

Default Value

FALSE

Remarks

This property indicates whether the class is currently active and can send or receive data.

If the UseConnection configuration setting is set to True, then a local association (connection) to the remote host also is created.

Note: Use the Activate or Deactivate method to control whether the class is active.

This property is not available at design time.

Data Type

Boolean

DontRoute Property (ICMP Class)

If this property is set to True, it forces the socket to send data directly to the interface (no routing).

Syntax

ANSI (Cross Platform)
int GetDontRoute();
int SetDontRoute(int bDontRoute); Unicode (Windows) BOOL GetDontRoute();
INT SetDontRoute(BOOL bDontRoute);
int ipworks_icmp_getdontroute(void* lpObj);
int ipworks_icmp_setdontroute(void* lpObj, int bDontRoute);
bool GetDontRoute();
int SetDontRoute(bool bDontRoute);

Default Value

FALSE

Remarks

If this property is set to True, it forces the socket to send data directly to the interface (no routing). Normally, IP sockets send packets of data through routers and gateways until they reach the final destination. If this property is set to True, then data will be delivered on the local subnet only.

This property is not available at design time.

Data Type

Boolean

LocalHost Property (ICMP Class)

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

Syntax

ANSI (Cross Platform)
char* GetLocalHost();
int SetLocalHost(const char* lpszLocalHost); Unicode (Windows) LPWSTR GetLocalHost();
INT SetLocalHost(LPCWSTR lpszLocalHost);
char* ipworks_icmp_getlocalhost(void* lpObj);
int ipworks_icmp_setlocalhost(void* lpObj, const char* lpszLocalHost);
QString GetLocalHost();
int SetLocalHost(QString qsLocalHost);

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 class initiate connections (or accept in the case of server classs) only through that interface.

If the class 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.

Data Type

String

MessageSubType Property (ICMP Class)

This property is the subtype of the ICMP message (part of the ICMP header).

Syntax

ANSI (Cross Platform)
int GetMessageSubType();
int SetMessageSubType(int iMessageSubType); Unicode (Windows) INT GetMessageSubType();
INT SetMessageSubType(INT iMessageSubType);
int ipworks_icmp_getmessagesubtype(void* lpObj);
int ipworks_icmp_setmessagesubtype(void* lpObj, int iMessageSubType);
int GetMessageSubType();
int SetMessageSubType(int iMessageSubType);

Default Value

0

Remarks

This property contains the subtype of the ICMP message (part of the ICMP header). The ICMP message subtype (also referred to as "code") is a byte value representing the message subclass. Its meaning is associated with the MessageType.

Types and subtypes of ICMP messages are defined in the various internet RFCs and other documentation associated with Transmission Control Protocol (TCP)/IP.

Data Type

Integer

MessageType Property (ICMP Class)

This property includes the type of the ICMP message (part of the ICMP header).

Syntax

ANSI (Cross Platform)
int GetMessageType();
int SetMessageType(int iMessageType); Unicode (Windows) INT GetMessageType();
INT SetMessageType(INT iMessageType);
int ipworks_icmp_getmessagetype(void* lpObj);
int ipworks_icmp_setmessagetype(void* lpObj, int iMessageType);
int GetMessageType();
int SetMessageType(int iMessageType);

Default Value

0

Remarks

This property contains the type of the ICMP message (part of the ICMP header). The ICMP message type is a byte value representing the message class. The message type defines the structure and meaning of the message data assigned to DataToSend.

Types for ICMP messages are defined in the various internet RFCs and other documentation associated with Transmission Control Protocol (TCP/IP). The following are a few examples of ICMP message types:

0 Echo reply ("ping" reply).
3 Destination unreachable.
4 Source quench.
5 Redirect (change a route).
8 Echo request ("ping" request).
11 Time exceeded for datagram.
12 Parameter problem on datagram.
13 Timestamp request.
14 Timestamp reply.
17 Address mask request.
18 Address mask reply.

Data Type

Integer

RemoteHost Property (ICMP Class)

This property includes the address of the RemoteHost. Domain names are resolved to IP addresses.

Syntax

ANSI (Cross Platform)
char* GetRemoteHost();
int SetRemoteHost(const char* lpszRemoteHost); Unicode (Windows) LPWSTR GetRemoteHost();
INT SetRemoteHost(LPCWSTR lpszRemoteHost);
char* ipworks_icmp_getremotehost(void* lpObj);
int ipworks_icmp_setremotehost(void* lpObj, const char* lpszRemoteHost);
QString GetRemoteHost();
int SetRemoteHost(QString qsRemoteHost);

Default Value

""

Remarks

This property specifies the IP address (IP number in dotted internet format) or the domain name of the remote host.

If this property is set to 255.255.255.255, the class broadcasts data on the local subnet.

If this property is set to a domain name, a DNS request is initiated. Upon successful termination of the request, the property is set to the corresponding address. If the search is not successful, the class fails with an error.

If UseConnection is True, this property must be set before the class is activated (Active is set to True).

Data Type

String

Timeout Property (ICMP Class)

A timeout for the class.

Syntax

ANSI (Cross Platform)
int GetTimeout();
int SetTimeout(int iTimeout); Unicode (Windows) INT GetTimeout();
INT SetTimeout(INT iTimeout);
int ipworks_icmp_gettimeout(void* lpObj);
int ipworks_icmp_settimeout(void* lpObj, int iTimeout);
int GetTimeout();
int SetTimeout(int iTimeout);

Default Value

0

Remarks

If the Timeout property is set to 0, all operations return immediately, potentially failing with an 'WOULDBLOCK' error if data can't be sent or received immediately.

If Timeout is set to a positive value, the class will automatically retry each operation that would otherwise result in a 'WOULDBLOCK' error 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.

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 0 (asynchronous operation).

Data Type

Integer

TimeToLive Property (ICMP Class)

This property includes the time-to-live (TTL) value for the ICMP packets sent by the class.

Syntax

ANSI (Cross Platform)
int GetTimeToLive();
int SetTimeToLive(int iTimeToLive); Unicode (Windows) INT GetTimeToLive();
INT SetTimeToLive(INT iTimeToLive);
int ipworks_icmp_gettimetolive(void* lpObj);
int ipworks_icmp_settimetolive(void* lpObj, int iTimeToLive);
int GetTimeToLive();
int SetTimeToLive(int iTimeToLive);

Default Value

0

Remarks

This method contains the time-to-live (TTL) value for the ICMP packets sent by the class. The TTL field of the ICMP packet is a counter limiting the lifetime of a packet.

Each router (or other module) that handles a packet decrements the TTL field by one or more if it holds the packet for more than one second. Thus, the TTL value is effectively a hop count limit on how far a datagram can propagate through the internet. When the TTL value is reduced to zero (or less), the packet is discarded.

If the value of the property is set to zero, then the default TTL value of the underlying Transmission Control Protocol (TCP)/IP subsystem will be used.

This property is not available at design time.

Data Type

Integer

Activate Method (ICMP Class)

This method enables sending and receiving of data.

Syntax

ANSI (Cross Platform)
int Activate();

Unicode (Windows)
INT Activate();
int ipworks_icmp_activate(void* lpObj);
int Activate();

Remarks

This method enables sending and receiving of data. When called, the class will create a communication endpoint (socket) that can be used for sending and receiving ICMP messages. This method must be called before using the class to send and receive data.

If the UseConnection configuration setting is set to true, then a local association (connection) to the remote host also is created.

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.)

Config Method (ICMP Class)

Sets or retrieves a configuration setting.

Syntax

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

Unicode (Windows)
LPWSTR Config(LPCWSTR lpszConfigurationString);
char* ipworks_icmp_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.

Deactivate Method (ICMP Class)

This method disables sending and receiving of data.

Syntax

ANSI (Cross Platform)
int Deactivate();

Unicode (Windows)
INT Deactivate();
int ipworks_icmp_deactivate(void* lpObj);
int Deactivate();

Remarks

This method disables sending and receiving of data. When called, the class will destroy the existing socket and disable data communications.

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.)

DoEvents Method (ICMP Class)

Processes events from the internal message queue.

Syntax

ANSI (Cross Platform)
int DoEvents();

Unicode (Windows)
INT DoEvents();
int ipworks_icmp_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.)

PauseData Method (ICMP Class)

This method pauses data reception.

Syntax

ANSI (Cross Platform)
int PauseData();

Unicode (Windows)
INT PauseData();
int ipworks_icmp_pausedata(void* lpObj);
int PauseData();

Remarks

This method pauses data reception when called. While data reception is paused, the DataIn event will not fire. Call ProcessData to reenable data reception.

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.)

ProcessData Method (ICMP Class)

This method reenables data reception after a call to PauseData .

Syntax

ANSI (Cross Platform)
int ProcessData();

Unicode (Windows)
INT ProcessData();
int ipworks_icmp_processdata(void* lpObj);
int 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.

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.)

Reset Method (ICMP Class)

Reset the class.

Syntax

ANSI (Cross Platform)
int Reset();

Unicode (Windows)
INT Reset();
int ipworks_icmp_reset(void* lpObj);
int Reset();

Remarks

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

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.)

ResolveRemoteHost Method (ICMP Class)

Resolves the hostname in RemoteHost to an IP address.

Syntax

ANSI (Cross Platform)
int ResolveRemoteHost();

Unicode (Windows)
INT ResolveRemoteHost();
int ipworks_icmp_resolveremotehost(void* lpObj);
int ResolveRemoteHost();

Remarks

This method resolves the hostname specified by RemoteHost to an IP address. The resolved value is available in the RemoteHost property after this method returns.

In most cases calling this method is not necessary, the class will resolve the hostname automatically when necessary. If DelayHostResolution is true this method may be called to manually resolve RemoteHost if desired.

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 (ICMP Class)

This method sends data to the remote host.

Syntax

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

Unicode (Windows)
INT Send(LPCSTR lpText, INT lenText);
int ipworks_icmp_send(void* lpObj, const char* lpText, int lenText);
int Send(QByteArray qbaText);

Remarks

This method sends data to the remote host. Calling this method is equivalent to setting the DataToSend property to Text.

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.)

SendBytes Method (ICMP Class)

This method sends data to the remote host.

Syntax

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

Unicode (Windows)
INT SendBytes(LPCSTR lpData, INT lenData);
int ipworks_icmp_sendbytes(void* lpObj, const char* lpData, int lenData);
int SendBytes(QByteArray qbaData);

Remarks

This method sends data to the remote host. Calling this method is equivalent to calling the SendBytes/SendText method.

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.)

SendText Method (ICMP Class)

This method sends data to the remote host.

Syntax

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

Unicode (Windows)
INT SendText(LPCWSTR lpszText);
int ipworks_icmp_sendtext(void* lpObj, const char* lpszText);
int SendText(const QString& qsText);

Remarks

This method sends data to the remote host. Calling this method is equivalent to calling the SendBytes/SendText method.

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.)

DataIn Event (ICMP Class)

This event is fired when a new ICMP messages come in.

Syntax

ANSI (Cross Platform)
virtual int FireDataIn(ICMPDataInEventParams *e);
typedef struct {
int MessageType;
int MessageSubType;
const char *MessageData; int lenMessageData;
int Checksum;
const char *SourceAddress; int reserved; } ICMPDataInEventParams;
Unicode (Windows) virtual INT FireDataIn(ICMPDataInEventParams *e);
typedef struct {
INT MessageType;
INT MessageSubType;
LPCSTR MessageData; INT lenMessageData;
INT Checksum;
LPCWSTR SourceAddress; INT reserved; } ICMPDataInEventParams;
#define EID_ICMP_DATAIN 1

virtual INT IPWORKS_CALL FireDataIn(INT &iMessageType, INT &iMessageSubType, LPSTR &lpMessageData, INT &lenMessageData, INT &iChecksum, LPSTR &lpszSourceAddress);
class ICMPDataInEventParams {
public:
  int MessageType();

  int MessageSubType();

  const QByteArray &MessageData();

  int Checksum();

  const QString &SourceAddress();

  int EventRetVal();
  void SetEventRetVal(int iRetVal);
};
// To handle, connect one or more slots to this signal. void DataIn(ICMPDataInEventParams *e);
// Or, subclass ICMP and override this emitter function. virtual int FireDataIn(ICMPDataInEventParams *e) {...}

Remarks

The MessageType parameter shows the type of the ICMP messages and the MessageSubType parameter shows its subtype.

The MessageData parameter contains the message data.

The Checksum parameter is True or False depending on the ICMP checksum validation on the message.

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.

Error Event (ICMP Class)

Information about errors during data delivery.

Syntax

ANSI (Cross Platform)
virtual int FireError(ICMPErrorEventParams *e);
typedef struct {
int ErrorCode;
const char *Description; int reserved; } ICMPErrorEventParams;
Unicode (Windows) virtual INT FireError(ICMPErrorEventParams *e);
typedef struct {
INT ErrorCode;
LPCWSTR Description; INT reserved; } ICMPErrorEventParams;
#define EID_ICMP_ERROR 2

virtual INT IPWORKS_CALL FireError(INT &iErrorCode, LPSTR &lpszDescription);
class ICMPErrorEventParams {
public:
  int ErrorCode();

  const QString &Description();

  int EventRetVal();
  void SetEventRetVal(int iRetVal);
};
// To handle, connect one or more slots to this signal. void Error(ICMPErrorEventParams *e);
// Or, subclass ICMP and override this emitter function. virtual int FireError(ICMPErrorEventParams *e) {...}

Remarks

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

ErrorCode contains an error code and Description 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 (ICMP Class)

Fired when the class is ready to send data.

Syntax

ANSI (Cross Platform)
virtual int FireReadyToSend(ICMPReadyToSendEventParams *e);
typedef struct { int reserved; } ICMPReadyToSendEventParams;
Unicode (Windows) virtual INT FireReadyToSend(ICMPReadyToSendEventParams *e);
typedef struct { INT reserved; } ICMPReadyToSendEventParams;
#define EID_ICMP_READYTOSEND 3

virtual INT IPWORKS_CALL FireReadyToSend();
class ICMPReadyToSendEventParams {
public:
  int EventRetVal();
  void SetEventRetVal(int iRetVal);
};
// To handle, connect one or more slots to this signal. void ReadyToSend(ICMPReadyToSendEventParams *e);
// Or, subclass ICMP and override this emitter function. virtual int FireReadyToSend(ICMPReadyToSendEventParams *e) {...}

Remarks

The ReadyToSend event indicates that the underlying TCP/IP subsystem is ready to accept data after a failed DataToSend.

Config Settings (ICMP Class)

The class 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 class, access to these internal properties is provided through the Config method.

ICMP Config Settings

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 class 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.

DontFragment:   Whether the DontFragment control flag is set.

When set to True, the DontFragment control flag in the IP header will be set.

The default value is False.

IcmpDllTimeout:   The timeout for the class when using the icmp.dll.

The class will wait for the operation to complete before returning control. If IcmpDllTimeout expires, and the operation is not yet complete, the class fails with an error. IcmpDllTimeout must be set to a positive value.

The default value for IcmpDllTimeout is 60 seconds.

Note: This configuration setting is valid only when UseICMPDLL is set to True.

MaxMessageSize:   The maximum length of the messages that can be received.

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

MulticastTTL:   The time to live (TTL) value for multicast ICMP packets sent by the component.

When sending multicast packets, the setting specifies the time-to-live (TTL) field. The TTL field of the ICMP packet is a counter limiting the lifetime of a packet.

Each router (or other module) that handles a packet decrements the TTL field by one or more if it holds the packet for more than one second. Thus, the TTL is effectively a hop count limit on how far a datagram can propagate through the internet. When the TTL is reduced to zero (or less), the packet is discarded.

By default, the default TTL value of the underlying Transmission Control Protocol (TCP)/IP subsystem will be used.

ReceiveAllMode:   Enables a socket to receive all IPv4 or IPv6 packets on the network.

This setting specifies the ReceiveAll mode for the socket. The following modes are available:

ValueDescription
-1 (default)The socket option is left unspecified.
0Do not receive all network traffic.
1Receive all network traffic. This enables the promiscuous mode on the network interface card (NIC). On a LAN segment with a network hub, a NIC that supports the promiscuous mode will capture all IPv4 or IPv6 traffic on the LAN, including traffic between other computers on the same LAN segment.
2Receive only socket-level network traffic (this feature may not be implemented by your Windows installation).
3Receive only IP-level network traffic. This option does not enable the promiscuous mode on the NIC. This option affects packet processing only at the IP level. The NIC still receives only those packets directed to its configured unicast and multicast addresses. A socket with this option enabled, however, not only will receive packets directed to specific IP addresses, but also will receive all the IPv4 or IPv6 packets the NIC receives.

TimeoutInMilliseconds:   The timeout is treated as milliseconds.

Setting TimeoutInMilliseconds to True causes the class to use the value in the IcmpDllTimeout configuration setting as milliseconds instead of seconds, which is the default.

Note: This setting is valid only when UseICMPDLL is set to True.

UseConnection:   Determines whether to use a connected socket.

UseConnection specifies whether the class 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 class will send and receive data only to and from the specified destination.

The default value for this setting is False.

UseICMPDLL:   Use the icmp.dll included on Windows Systems.

Setting UseICMPDLL to True causes the class to use the icmp.dll on Windows 9x or on later machines. This sometimes enables access to raw sockets when permissions for standard operations are prohibited.

UseIPHLPDLL:   Use the iphlpapi.dll included on Windows Systems.

Setting UseIPHLPDLL to True causes the class to use the iphlpapi.dll on Windows XP or on later machines. This sometimes enables access to raw sockets when permissions for standard operations are prohibited.

Note: If both this and UseICMPDLL are enabled, the iphlpapi.dll will take precedence.

UseIPv6:   Whether to use IPv6.

When set to 0 (default), the class will use IPv4 exclusively. When set to 1, the class will use IPv6 exclusively. To instruct the class to prefer IPv6 addresses, but use IPv4 if IPv6 is not supported on the system, this setting should be set to 2. The default value is 0. Possible values are:

0 IPv4 Only
1 IPv6 Only
2 IPv6 with IPv4 fallback

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 class 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 class 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.

CodePage:   The system code page used for Unicode to Multibyte translations.

The default code page is Unicode UTF-8 (65001).

The following is a list of valid code page identifiers:

IdentifierName
037IBM EBCDIC - U.S./Canada
437OEM - United States
500IBM EBCDIC - International
708Arabic - ASMO 708
709Arabic - ASMO 449+, BCON V4
710Arabic - Transparent Arabic
720Arabic - Transparent ASMO
737OEM - Greek (formerly 437G)
775OEM - Baltic
850OEM - Multilingual Latin I
852OEM - Latin II
855OEM - Cyrillic (primarily Russian)
857OEM - Turkish
858OEM - Multilingual Latin I + Euro symbol
860OEM - Portuguese
861OEM - Icelandic
862OEM - Hebrew
863OEM - Canadian-French
864OEM - Arabic
865OEM - Nordic
866OEM - Russian
869OEM - Modern Greek
870IBM EBCDIC - Multilingual/ROECE (Latin-2)
874ANSI/OEM - Thai (same as 28605, ISO 8859-15)
875IBM EBCDIC - Modern Greek
932ANSI/OEM - Japanese, Shift-JIS
936ANSI/OEM - Simplified Chinese (PRC, Singapore)
949ANSI/OEM - Korean (Unified Hangul Code)
950ANSI/OEM - Traditional Chinese (Taiwan; Hong Kong SAR, PRC)
1026IBM EBCDIC - Turkish (Latin-5)
1047IBM EBCDIC - Latin 1/Open System
1140IBM EBCDIC - U.S./Canada (037 + Euro symbol)
1141IBM EBCDIC - Germany (20273 + Euro symbol)
1142IBM EBCDIC - Denmark/Norway (20277 + Euro symbol)
1143IBM EBCDIC - Finland/Sweden (20278 + Euro symbol)
1144IBM EBCDIC - Italy (20280 + Euro symbol)
1145IBM EBCDIC - Latin America/Spain (20284 + Euro symbol)
1146IBM EBCDIC - United Kingdom (20285 + Euro symbol)
1147IBM EBCDIC - France (20297 + Euro symbol)
1148IBM EBCDIC - International (500 + Euro symbol)
1149IBM EBCDIC - Icelandic (20871 + Euro symbol)
1200Unicode UCS-2 Little-Endian (BMP of ISO 10646)
1201Unicode UCS-2 Big-Endian
1250ANSI - Central European
1251ANSI - Cyrillic
1252ANSI - Latin I
1253ANSI - Greek
1254ANSI - Turkish
1255ANSI - Hebrew
1256ANSI - Arabic
1257ANSI - Baltic
1258ANSI/OEM - Vietnamese
1361Korean (Johab)
10000MAC - Roman
10001MAC - Japanese
10002MAC - Traditional Chinese (Big5)
10003MAC - Korean
10004MAC - Arabic
10005MAC - Hebrew
10006MAC - Greek I
10007MAC - Cyrillic
10008MAC - Simplified Chinese (GB 2312)
10010MAC - Romania
10017MAC - Ukraine
10021MAC - Thai
10029MAC - Latin II
10079MAC - Icelandic
10081MAC - Turkish
10082MAC - Croatia
12000Unicode UCS-4 Little-Endian
12001Unicode UCS-4 Big-Endian
20000CNS - Taiwan
20001TCA - Taiwan
20002Eten - Taiwan
20003IBM5550 - Taiwan
20004TeleText - Taiwan
20005Wang - Taiwan
20105IA5 IRV International Alphabet No. 5 (7-bit)
20106IA5 German (7-bit)
20107IA5 Swedish (7-bit)
20108IA5 Norwegian (7-bit)
20127US-ASCII (7-bit)
20261T.61
20269ISO 6937 Non-Spacing Accent
20273IBM EBCDIC - Germany
20277IBM EBCDIC - Denmark/Norway
20278IBM EBCDIC - Finland/Sweden
20280IBM EBCDIC - Italy
20284IBM EBCDIC - Latin America/Spain
20285IBM EBCDIC - United Kingdom
20290IBM EBCDIC - Japanese Katakana Extended
20297IBM EBCDIC - France
20420IBM EBCDIC - Arabic
20423IBM EBCDIC - Greek
20424IBM EBCDIC - Hebrew
20833IBM EBCDIC - Korean Extended
20838IBM EBCDIC - Thai
20866Russian - KOI8-R
20871IBM EBCDIC - Icelandic
20880IBM EBCDIC - Cyrillic (Russian)
20905IBM EBCDIC - Turkish
20924IBM EBCDIC - Latin-1/Open System (1047 + Euro symbol)
20932JIS X 0208-1990 & 0121-1990
20936Simplified Chinese (GB2312)
21025IBM EBCDIC - Cyrillic (Serbian, Bulgarian)
21027Extended Alpha Lowercase
21866Ukrainian (KOI8-U)
28591ISO 8859-1 Latin I
28592ISO 8859-2 Central Europe
28593ISO 8859-3 Latin 3
28594ISO 8859-4 Baltic
28595ISO 8859-5 Cyrillic
28596ISO 8859-6 Arabic
28597ISO 8859-7 Greek
28598ISO 8859-8 Hebrew
28599ISO 8859-9 Latin 5
28605ISO 8859-15 Latin 9
29001Europa 3
38598ISO 8859-8 Hebrew
50220ISO 2022 Japanese with no halfwidth Katakana
50221ISO 2022 Japanese with halfwidth Katakana
50222ISO 2022 Japanese JIS X 0201-1989
50225ISO 2022 Korean
50227ISO 2022 Simplified Chinese
50229ISO 2022 Traditional Chinese
50930Japanese (Katakana) Extended
50931US/Canada and Japanese
50933Korean Extended and Korean
50935Simplified Chinese Extended and Simplified Chinese
50936Simplified Chinese
50937US/Canada and Traditional Chinese
50939Japanese (Latin) Extended and Japanese
51932EUC - Japanese
51936EUC - Simplified Chinese
51949EUC - Korean
51950EUC - Traditional Chinese
52936HZ-GB2312 Simplified Chinese
54936Windows XP: GB18030 Simplified Chinese (4 Byte)
57002ISCII Devanagari
57003ISCII Bengali
57004ISCII Tamil
57005ISCII Telugu
57006ISCII Assamese
57007ISCII Oriya
57008ISCII Kannada
57009ISCII Malayalam
57010ISCII Gujarati
57011ISCII Punjabi
65000Unicode UTF-7
65001Unicode UTF-8

The following is a list of valid code page identifiers for Mac OS only:

IdentifierName
1ASCII
2NEXTSTEP
3JapaneseEUC
4UTF8
5ISOLatin1
6Symbol
7NonLossyASCII
8ShiftJIS
9ISOLatin2
10Unicode
11WindowsCP1251
12WindowsCP1252
13WindowsCP1253
14WindowsCP1254
15WindowsCP1250
21ISO2022JP
30MacOSRoman
10UTF16String
0x90000100UTF16BigEndian
0x94000100UTF16LittleEndian
0x8c000100UTF32String
0x98000100UTF32BigEndian
0x9c000100UTF32LittleEndian
65536Proprietary

LicenseInfo:   Information about the current license.

When queried, this setting will return a string containing information about the license this instance of a class 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.
ProcessIdleEvents:   Whether the class uses its internal event loop to process events when the main thread is idle.

If set to False, the class will not fire internal idle events. Set this to False to use the class in a background thread on Mac OS. By default, this setting is True.

SelectWaitMillis:   The length of time in milliseconds the class will wait when DoEvents is called if there are no events to process.

If there are no events to process when DoEvents is called, the class will wait for the amount of time specified here before returning. The default value is 20.

UseInternalSecurityAPI:   Tells the class whether or not to use the system security libraries or an internal implementation.

By default the class will use the system security libraries to perform cryptographic functions where applicable. Setting this to true tells the class to use the internal implementation instead of using the system's security API.

Trappable Errors (ICMP 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.

ICMP Errors

104   The class is already Active.
107   Cannot change the LocalHost at this time. A connection is in progress.
109   The class must be Active for this operation.
112   Cannot change MaxMessageSize while ICMP is Active.
114   Cannot change RemoteHost when UseConnection is set and the class is Active.
117   Cannot change UseConnection while the class is Active.
118   The message cannot be longer than MaxMessageSize.
119   The message is too short.
120   Cannot create ICMP handle.

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).

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IPWorks 2022 C++ Edition - Version 22.0 [Build 8369]