Function v4l::v4l2::api::ioctl

pub unsafe fn ioctl(
    fd: c_int, 
    request: _IOC_TYPE, 
    argp: *mut c_void
) -> Result<()>

A convenience wrapper around v4l2_ioctl.

In case of errors, the last OS error will be reported, aka errno on Linux.

Arguments

• fd - File descriptor
• request - IO control code (see codes)
• argp - Pointer to memory region holding the argument type

Safety

For maximum flexibility, argp must be a raw pointer. Thus, the entire function is unsafe.

Example

extern crate v4l;

use std::mem;

use v4l::v4l_sys::*;
use v4l::v4l2;

let fd = v4l2::open("/dev/video0", libc::O_RDWR);
let mut v4l2_caps: v4l2_capability;
unsafe {
    v4l2_caps = mem::zeroed();
}

if let Ok(fd) = fd {
    unsafe {
        v4l2::ioctl(fd, v4l2::vidioc::VIDIOC_QUERYCAP,
                    &mut v4l2_caps as *mut _ as *mut std::os::raw::c_void);
    }
}