I am using the CVI TCP support package with my application and I am curious about the following code: ClientTCPReadchar * buffer;int messageSize;int bytesToRead;int bytesRead; /* Find messageSize and allocate buffer appropriately... */ bytesToRead = messageSize; while (bytesToRead > 0) { bytesRead = ClientTCPRead (connectionHandle, &buffer[messageSize - bytesToRead], bytesToRead, 0); bytesToRead -= bytesRead; } Ok, this works if you are passing char array elements, but what if you were passing a structure of arbitrary size? If you read/write the bytes read/written and you don't get all the data you requested, what do you do at this point to retrieve the rest of the subsequent data? For example, replace the 'buffer' array of type char with a structure of a user-defined type with a size of 100 bytes or something to that extent. You make a read/write request and read/wrote less than 100 bytes. How do you get the rest of the data? Does CVI do something in the background? I could use this code with multiple structures, but then again, a particular member of a structure is not the size of a byte like a char. Much appreciated, Chris

The solution is to use a char casted pointer to allocate the transmitted data. The only catch is that buffer must be a pointer to the data type of the structure before a char cast can be used for a successful program compilation. Thank you for your help. Chris

LabWindows/CVI

Passing a single structure via Client/ServerTCPRead/Write functions and insuring that all the data is transferred

Solved!

Hi Decoy,

what is the diffrence between twos code,Please explain me,Iam Right now doing Server-client Project.

bytesRead = ClientTCPRead (connectionHandle, &buffer[messageSize - bytesToRead], bytesToRead, 0);


   read = ClientTCPRead( connection, (unsigned char *)buffer + read_total, sizeof( message ) - read_total, 10 )