| LEADTOOLS DICOM C DLL Help > Callback Functions > RECEIVECECHOREQUESTCALLBACK | 
#include "ltdic.h"
L_VOID pEXT_CALLBACK Your Function(hNet, nPresentationID, nMessageID, pszClass, pUserData)
| HDICOMNET hNet; | /* a DICOM Network handle */ | 
| L_UCHAR nPresentationID; | /* presentation ID */ | 
| L_UINT16 nMessageID; | /* message ID */ | 
| L_TCHAR * pszClass; | /* class type */ | 
| L_VOID * pUserData; | /* pointer to additional data */ | 
Notifies a connection that a C-ECHO-REQ command was received. This function is available in the Medical Suite Toolkit.
| Parameter | Description | 
| hNet | A DICOM Network handle. | 
| nPresentationID | Presentation ID. The presentation ID provides information about both the class type of the data and the transfer syntax to use when transferring the data. | 
| nMessageID | Message ID. Each message sent by a member of a connection should have a unique ID. Since a member of a connection may send several messages, this ID allows that member to identify when a specific request has been completed. | 
| pszClass | Class affected by the request. This will be an SOP Class or an SOP MetaClass. | 
| pUserData | Void pointer that you can use to access a variable or structure containing data that your callback function needs. This gives you a way to receive data indirectly from the function that uses this callback function. | 
| 
 | Keep in mind that this is a void pointer, which must be cast to the appropriate data type within your callback function. | 
Returns
None.
Comments
A call to this function is generated on a peer member of a connection when L_DicomSendCEchoRequest is called.
To use this callback function, RECEIVECECHOREQUESTCALLBACK must be set using L_DicomSetCallback.
Required DLLs and Libraries
| LTDIC For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application | 
Win32, x64
See Also
| Functions: | L_DicomSendCEchoRequest, L_DicomSendCEchoResponse, RECEIVECECHORESPONSECALLBACK | 
| Topics: | 
Example
For an example, refer to L_DicomSendCEchoResponse.