Before understanding the operating system’s system calls, it is very important to understand kernel mode and user mode. There are total 2 modes in any operating system, each of the work performed by the operating system is happening on one of these two modes.
- Kernel Mode:- Kernel mode is the privileged and powerful mode in an operating system, which can access any hardware resource of the computer system or the information stored in the memory. Usually the most important programs and device drivers of the operating system are executed by kernel mode and if a program crashes in kernel mode then it can affect the whole operating system which can shut down the whole computer.
- User Mode:- Programs executed in user mode cannot directly access the hardware resources of the whole system and all the data stored in the memory. If a program crashes in the user mood, it does not affect the operating system. Usually in user mode, normal programs and instructions given by the user are executed.
System Call in Operating System in Hindi
System Call in Operating System :- System call is a mechanism, which provides an interface between the user mode and kernel mode of the operating system, that is, in simple words, when a program is executing in the user mode of the computer. If this occurs, it requires the permission of the kernel to access any data stored in memory or any hardware device. Therefore a system call is needed in the operating system, which provides an interface between the program being executed in user mode and the kernel.
When a program makes a system call, it switches from user mode to kernel mode. This process is called context switch. After that the kernel provides the necessary resources to the program and the program again runs from kernel mode to user mode.
Services Provided by System Calls in Hindi
Services Provided by System Calls: – The following types of services are provided to the program through system calls.
- System calls help to initiate and manage the execution of a program.
- It helps in managing the information stored in the main memory of the computer called random access memory or RAM.
- It helps to access and manage files and directories.
- System calls help to handle hardware devices and input/output devices.
- System calls also play an important role in exchanging information between different computers through networking.
Type of System Calls in Hindi
Type of System Calls in Hindi :- There are mainly five types of system calls.
- Process Control:- When a program is in execution state then it is called process, that is, when a program is executing in the computer’s CPU then it is called process. The processes related to the creation of a new process and the termination of a process are completed through process control system calls.
- File Management:- This type of system call is used for tasks related to accessing, editing, updating and deleting files.
- Device Management:- These system calls are used to work with various hardware devices such as input or output devices, printers, scanners etc.
- Information Maintenance:- This system call handles the instructions given by the user or the transfer of information between the programs and the operating system.
- Communication:- This system call helps in establishing a communication system by exchanging information between different devices.
Conclusion System Calls in HindiSystem call is used to switch from user mode to kernel mode by the program executing in the CPU of the computer. A program requires access to various hardware devices to access the information stored in memory and to perform input-output operations. But the program running in user mode switches from user mode to kernel mode using system calls to perform these tasks and then completes its execution process.
There are mainly five types of system calls, which help in various ways from starting the execution of a program to completing its execution.