What is a system call in an operating system?
a) A way for programs to request services from the operating system
b) A technique for scheduling CPU processes
c) A method for transferring data between devices
d) A way to manage virtual memory
Answer:
a) A way for programs to request services from the operating system
Explanation:
A system call is a mechanism by which user programs request services from the operating system’s kernel. It allows programs to interact with the OS for tasks such as file manipulation, process control, memory management, and device handling.
System calls provide an interface between the user-mode applications and the kernel-mode components of the operating system, enabling programs to execute privileged instructions such as opening files or allocating memory.
Common system calls include operations like open(), read(), write(), and close() for file handling. System calls are an essential part of modern operating systems, enabling programs to use the system’s resources securely and efficiently.