ABSTRACT
An operating system (OS) provides many tools and facilities to make a computer usable. However, the most basic and fundamental set of services is the system calls, specific routines in the operating system kernel that are directly accessible to application programs. There are over 300 system calls in Linux with a kernel-defined number starting from 1. Each system call also has a meaningful name and a symbolic constant in the form SYS_name for its number. With a few exceptions, a system call name corresponds to the routine sys_name in the Linux kernel source code.
