Generates a wrapper function for an ioctl that passes no data to the kernel.

The arguments to this macro are:

• The function name
• The ioctl identifier
• The ioctl sequence number

The generated function has the following signature:

pub unsafe fn FUNCTION_NAME(fd: libc::c_int) -> Result<libc::c_int>

For a more in-depth explanation of ioctls, see ::sys::ioctl.

Example

The videodev2 driver on Linux defines the log_status ioctl as:

#define VIDIOC_LOG_STATUS         _IO('V', 70)

This can be implemented in Rust like:

# #[macro_use] extern crate nix;
ioctl_none!(log_status, b'V', 70);
fn main() {}