Function ioctl

pub unsafe fn ioctl<F: AsRawFd>(fd: &F, req: c_ulong) -> c_int

Run an ioctl with no arguments.

Arguments

• fd: an open file descriptor corresponding to the device on which to call the ioctl.
• req: a device-dependent request code.

Safety

The caller should ensure to pass a valid file descriptor and have the return value checked.

Examples

use vmm_sys_util::ioctl::ioctl;

const KVMIO: c_uint = 0xAE;
const KVM_API_VERSION: u32 = 12;
ioctl_io_nr!(KVM_GET_API_VERSION, KVMIO, 0x00);

let open_flags = O_RDWR | O_CLOEXEC;
let kvm_fd = unsafe { open("/dev/kvm\0".as_ptr() as *const c_char, open_flags) };

let ret = unsafe { ioctl(&File::from_raw_fd(kvm_fd), KVM_GET_API_VERSION()) };

assert_eq!(ret as u32, KVM_API_VERSION);