How to send byte aligned structures via UDP sockets?

Hello,

     I was curious as to how you send byte aligned structures via MATLAB'S UDP sockets. I am using MATLAB to interface with a C program that expects the following structure 

typedef struct{
  int     member_1;                      
        int  member_2;                  
  int  member_3;                            
  int     member_4;                            
  float   member_5;               
  float   member_6;                  
  float   member_7;                 
  float   member_8[256];       
} T_Mystruct;

The size of this structure in bytes is 1052 bytes which is under the windows MTU size for UDP packets. The issue is that this data needs to be all in one packet. If I construct the packet like this in matlab,( which i tired)

msg_1 = [ member_1,member_2,member_3,member_4];   
msg_2 = [ member_5,member_6,member_7];
msg_3 = member_8;

fwrite(udp_socket,msg_1, 'int32')
fwrite(udp_socket,msg_2, 'float32')  
fwrite(udp_socket,msg_3, 'float32')

this sends the right number of bytes but the wrong number of packets. Is there any way to condense this into one packet, that is byte aligned to the above format? I considered this:

packet = [msg_1,msg_2,msg_3];    
fwrite(udp_socket,packet,'????');

but then what do you put for the precision ? it would be nice to just tell it how many bytes to write as a "custom" precision . thank you for your time.