Programming :: RS232 Configuration Is Not Doing Do Wanted Operation

I am writing a program to send data over serial port but the sending and reading operation is not occurring as desired to be... Below you can see the read and write parts. Could you please help me to find where I am doing wrong...

Reading Part:

Code:

#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <termios.h>

[code]....

When I compile and run the above programs Reading part does not read the 13 bytes once it first reads 8 byte then 8 again then 2 and so on. It always divides the sent data...