Function nc::preadv [−][src]
pub fn preadv(
fd: i32,
vec: &mut [iovec_t],
pos_l: usize,
pos_h: usize
) -> Result<ssize_t, Errno>
Expand description
Read from a file descriptor without changing file offset.
let path = "/etc/passwd"; let ret = nc::open(path, nc::O_RDONLY, 0); assert!(ret.is_ok()); let fd = ret.unwrap(); let mut buf = [[0_u8; 64]; 4]; let capacity = 4 * 64; let mut iov = Vec::with_capacity(buf.len()); for ref mut item in (&mut buf).iter() { iov.push(nc::iovec_t { iov_len: item.len(), iov_base: item.as_ptr() as usize, }); } let iov_len = iov.len(); let ret = nc::preadv(fd, &mut iov, 0, iov_len - 1); assert!(ret.is_ok()); assert_eq!(ret, Ok(capacity as nc::ssize_t)); assert!(nc::close(fd).is_ok());