C program to shutdown the computer

In this article, you will learn how to shut down your computer system using a C program and get the code for doing so. The program to shutdown your system is provided for both Windows and Linux users. Here is the list of programs available:

Shutdown your Windows 7, 8, 10, or 11-based system.
Shutdown your system immediately.
Shutdown your Windows XP-based system.
Shutdown your Linux-based system.

Important: Before executing any of the programs given below, be sure to save all the opened files in your computer system. Because after running the program, your system will be shut down and all unsaved documents will be lost.

Now let's move on to the programs.

Computer shutdown in C

To shutdown your computer using C programming, just call the system() function, which will call the cmd (for Windows) or terminal (for Linux) to shutdown your computer.

Now let's go through the one-by-one C programming code to shutdown your computer for all platforms, such as Windows 7, Windows 8, Windows 10, Windows 11, Windows XP, or Linux-based. Let's first start with how to shutdown your computer using C programming code for Windows 7, 8, 10, and 11 users.

Computer Shutdown for Windows 7, 8, 10, and 11

This C program will shut down or turn off your computer system. This program is intended for Windows users, specifically those running Windows 7, Windows 8, Windows 10, or Windows 11.

#include<stdio.h>
#include<stdlib.h>
int main()
{
    system("C:\\Windows\\System32\\shutdown /s");
    return 0;
}

Note: By default, the function system() that calls the shutdown file from the path C:\Windows\\System32\, which will shut down your computer after 30 seconds.

Therefore, the program given below uses the timer to shut down as soon as possible.

Shutdown the system immediately using a C program

This program immediately shuts down the computer system. That is, here the timer is set to 0 seconds, so that your system gets turned off immediately.

#include<stdio.h>
#include<conio.h>
int main()
{
    system("C:\\Windows\\System32\\shutdown /s /t 0");
    return 0;
}

Shutdown Windows XP-based systems using a C program

If you have an operating system named Windows XP installed on your laptop or PC, then the following program is for you:

#include<stdio.h>
#include<stdlib.h>
int main()
{
    char ch;
    printf("Do You want to Shutdown your Computer (y/n): ");
    scanf("%c", &ch);
    if(ch=='y' || ch=='Y')
        system("C:\\Windows\\System32\\shutdown -s");
    return 0;
}

Here, this program asks the user whether he or she wants to shut down his or her computer system or not. If you want to shutdown, then press Y; otherwise, press any other key.

C Program to Shut Down a Linux Computer

This is the last program that was created for Linux users. So that if any Linux user is reading this article, then they can also find the code in C to shutdown his or her Linux-based system:

#include<stdio.h>
int main()
{
    system("shutdown -P now");
    return 0;
}

Note: To shutdown your computer (for Linux users), you need to be logged in as root. Or, to execute the above program, you must be logged in as the root user. Otherwise, you will get an error message like shutdown: need to be rooted.

Set timer before Shutdown for Linux User

You can also specify the timer to shut down your Linux-based system at a given (or defined) time. The above program uses "now" to shutdown the system right now. But instead "now," you can specify the timer. Here is the syntax:

system("shutdown -P number of minutes");

For example,

system("shutdown -P 5");