how to execute an external program using lib_mysqludf_sys when an UPDATE happens in mysql

how to execute an external program using lib_mysqludf_sys when an UPDATE
happens in mysql

I have used lib_mysqludf_sys to execute the following C++ programs
executable file in mysql
I executed: mysql> SELECT sys_exec('/home/eden/Desktop/ins_data');
It returned: sys_exec('/home/eden/Desktop/ins_data') 32512
Actually in my ins_data executable file i inserted a new row in to mysql
database. But after executing this it is not inserting any new row. Im not
understanding what output it is returning. Im using C++ connector program
to insert a new row.