Generates a wrapper function for an ioctl that writes data through a pointer to the kernel.

The arguments to this macro are:

• The function name
• The ioctl identifier
• The ioctl sequence number
• The data type passed by this ioctl

The generated function has the following signature:

pub unsafe fn FUNCTION_NAME(fd: libc::c_int, data: *const DATA_TYPE) -> Result<libc::c_int>

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

Example

# #[macro_use] extern crate nix;
# pub struct v4l2_audio {}
ioctl_write_ptr!(s_audio, b'V', 34, v4l2_audio);
# fn main() {}