Function nix::sys::sendfile::sendfile
pub fn sendfile(out_fd: RawFd, in_fd: RawFd, offset: Option<&mut off_t>, count: usize) -> Result<usize>The portability is definied by:
#[cfg(any(target_os = "android", target_os = "linux"))]Documentation
Copy up to count bytes to out_fd from in_fd starting at offset.
Returns a Result with the number of bytes written.
If offset is None, sendfile will begin reading at the current offset of in_fdand will
update the offset of in_fd. If offset is Some, sendfile will begin at the specified
offset and will not update the offset of in_fd. Instead, it will mutate offset to point to
the byte after the last byte copied.
in_fd must support mmap-like operations and therefore cannot be a socket.
For more information, see the sendfile(2) man page.