Macro ioctl_write_ptr 

macro_rules! ioctl_write_ptr {
    ($(#[$attr:meta])* $name:ident, $ioty:expr, $nr:expr, $ty:ty) => { ... };
}

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

ioctl_write_ptr!(s_audio, b'V', 34, v4l2_audio);