difference between execv() , spawnlpe()

Hi All
I want to use the functions

  execv() or spawnple() to execute a shell script file ( executable shell of course) . but I dont know what is the difference between them.

Also if somebody can help me in how to write those functions in the C code and when the execution of the script ends , does it come back to my C code again or exits to shell

thanks All

From the documentation:

The execv() function REPLACES the current process image with the new process image specified by path.

The spawn() function CREATES and EXECUTES a new child process named in path.

thanks for reply
so now I think I have to use spawn() , because Iam calling a .sh file in my image, without terminating other processes.