Synchronization between send / recv in sockets

Question

I have a server that sends data in the form of strings of various lengths (for example, 79.80.81.82)

I want to be able to receive exactly one record at a time. I split the records using (r), but because I don't know how many bytes I should get, Sometimes it combines the records and makes the process difficult for me.

Answer 1

I have two ideas for you:

• Use XML for the protocol. This way you know exactly when each message ends.
• Send the packet size in the header of each "packet", so you know how much to read from the socket for this particular packet.

Edit: Look at this dummy code for (2)

int buffer_size;
char* buffer;

read( socket, &buffer_size, sizeof(buffer_size)); 
buffer = (char*) malloc(packet_size);
read( socket, buffer, buffer_size );
// do something
free( buffer) ; 

EDIT: , , "read()", "read()" ing, .

, . XML. , XML parlty, XML, , , 0 "" .

Answer 2

?

, .

struct Message
{
  int dataSize;
  char data[256];
};

Answer 3

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Answer 4

Stream sockets do not support the idea of ​​“recording” - the abstraction they provide is a continuous stream.

You must implement a layer on top of them to provide “records”. It looks like you have already gone there, with a separator for the end of the record. Pseudo code to complete it:

create empty buffer;
forever {
    recv data and append to buffer;

    while (buffer contains end-of-record marker) {
        remove first record from buffer and process it;
        move remaining data to beginning of buffer;
    }
}