Member Avatar for murtazamzk 
#include <stdlib.h>
#include <stdio.h>
#include<conio.h>

void main()
{
int ch;
clrscr();
printf("\n\n~~~~~~~~~~~~~~~~~SHUTDOWN MENU~~~~~~~~~~~~~~~~~~~\n");
printf("1.Shutdown\n2.Restart\n3.Logoff\n4.Hibernate\n5.exit");
printf("\nEnter choice : ");
scanf("%d",&ch);
switch(ch)
{
  case 1:system("shutdown -s");
         break;
  case 2:system("shutdown -r");
         break;
  case 3:system("shutdown -l");
         break;
  case 4:system("shutdown -h");
         break;
  case 5:exit(1);
         break;
  default:printf("Invalid choice");
}
getch();
}
  • 7 Contributors
  • 8 Replies
  • 492 Views
  • 2 Years Discussion Span
  • Latest Post Latest Post by deceptikon

Dani AI

Generated

A few practical clarifications and a safer, native option.

The sample in the first post calls out to an OS command, which is the simplest route but is inherently OS‑specific and often blocked by modern privilege/UAC policies (which is why saw "Access is denied"). For a reliable, programmatic shutdown on Windows use the Win32 API and explicitly enable the shutdown privilege instead of shelling out. The snippet below demonstrates the minimum: enable SE_SHUTDOWN_NAME, call ExitWindowsEx, and report failures so you can diagnose permission problems.

/* Windows: enable shutdown privilege and request power-off */
#include <windows.h>
#include <stdio.h>

static BOOL enable_shutdown_privilege(void)
{
    HANDLE hToken;
    TOKEN_PRIVILEGES tp = {0};

    if (!OpenProcessToken(GetCurrentProcess(),
                          TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY, &hToken)) {
        fprintf(stderr, "OpenProcessToken failed: %lu\n", GetLastError());
        return FALSE;
    }

    tp.PrivilegeCount = 1;
    tp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
    if (!LookupPrivilegeValue(NULL, SE_SHUTDOWN_NAME, &tp.Privileges[0].Luid)) {
        fprintf(stderr, "LookupPrivilegeValue failed: %lu\n", GetLastError());
        CloseHandle(hToken);
        return FALSE;
    }

    AdjustTokenPrivileges(hToken, FALSE, &tp, 0, NULL, NULL);
    if (GetLastError() != ERROR_SUCCESS) {
        fprintf(stderr, "AdjustTokenPrivileges failed: %lu\n", GetLastError());
        CloseHandle(hToken);
        return FALSE;
    }

    CloseHandle(hToken);
    return TRUE;
}

int main(void)
{
    if (!enable_shutdown_privilege()) return 1;
    if (!ExitWindowsEx(EWX_SHUTDOWN | EWX_POWEROFF, SHTDN_REASON_MAJOR_APPLICATION)) {
        fprintf(stderr, "ExitWindowsEx failed: %lu\n", GetLastError());
        return 1;
    }
    return 0;
}

Cross‑platform notes: on Linux/Unix there is no single portable syscall for polite shutdown — distributions may use systemd (use the login1 D‑Bus API or systemctl poweroff with appropriate privileges) or require root for a reboot(2)/poweroff syscall. Any production tool that must shut down machines for arbitrary users should either run as a privileged service/daemon or use the platform’s authorized API (polkit/DBus on systemd systems).

Troubleshooting checklist (builds on points raised by , , ): use int main(void), check and log return codes and GetLastError/errno, run elevated to satisfy privileges, avoid force flags unless you accept data loss, and test in a VM before using on a real workstation.

Recommended Answers

All 8 Replies

Member Avatar for WaltP

And your question about this poor code is... what?

Member Avatar for Shankye

You want to show how to shutdown ??????????????????????

Edited by Shankye because: n/a
Member Avatar for Jason Giggs

And your question about this poor code is... what?

hi...why is the code poor? i mean, i didn't even know we could shutdown the pc using c.
can u please tell me a (better) way? Thanks

Member Avatar for Shankye

@Jason

conio.h it is not part of the C standard library,

clrscr also not standard function ..

And he not doing any magic, just giving his work to system..

Member Avatar for WaltP

It's poor because of

#include<conio.h>
void main()
clrscr();
getch();

And the formatting is only fair.

Member Avatar for Trentacle

Second what WaltP says, plus don't use scanf for interactive user input, check the return values of standard library functions, and use fflush(stdout) after printing a prompt that doesn't end with '\n' to make sure it gets printed.

1 is not a portable value to pass to exit(), and returning non-zero usually means that some error occurred. Selecting the "exit" function from the menu shouldn't result in an error.

Finally, I can't imagine what version of "shutdown" you're using if -s means "halt", -l means "log off", and -h means "hibernate".

Member Avatar for atulpust

when I run the code and press y it says access is denied. So what can I do?

Member Avatar for deceptikon

when I run the code and press y it says access is denied. So what can I do?

Log in with an account that has permission to shut the computer down and then run the program.

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