1 Rotation around the front-to-back axis is called roll. 2  Rotation around the side-to-side axis is called pitch. 3  Rotation around the vertical axis is called yaw.  The Ailerons Control Roll. On the outer rear edge of each wing, the two ailerons move in opposite directions, up and down, decreasing lift on one wing while increasing it on the other.
A System call is a mechanism used by an application for requesting a service from the operating system. Examples of the services provided by the operating system are allocation and deallocation of memory, reporting of current date and time etc.
Actual code for system_call entry point can be found in /usr/src/linux/kernel/sys_call.S Actual code for many of the system calls can be found in /usr/src/linux/kernel/sys.c, and the rest are found elsewhere. find is your friend. After the system call has executed, _ret_from_sys_call() is called.