●●● ●●●● 2.Operating-System Structures 9908 ●●●● 2.1 Operating System Services 2.2 User Operating System Interface 2. 3 System Calls 2. 4 Types of System Calls ·24 System Programs 2.6 Operating System Design and Implementation 2.7 Operating System Structure ●28 Virtual machines 2.9 Operating System Generation 2.10 System Boot3 2. Operating-System Structures ⚫ 2.1 Operating System Services ⚫ 2.2 User Operating System Interface ⚫ 2.3 System Calls ⚫ 2.4 Types of System Calls ⚫ 2.4 System Programs ⚫ 2.6 Operating System Design and Implementation ⚫ 2.7 Operating System Structure ⚫ 2.8 Virtual Machines ⚫ 2.9 Operating System Generation ⚫ 2.10 System Boot