Expand Out wrapper and use it in utsname.

src/header/sys_utsname/mod.rs

@@ -2,12 +2,14 @@
 
 use crate::{
     error::ResultExt,
+    out::Out,
     platform::{Pal, Sys, types::*},
 };
 
 pub const UTSLENGTH: usize = 65;
 
 #[repr(C)]
+#[derive(Clone, Copy, Debug, OutProject)]
 pub struct utsname {
     pub sysname: [c_char; UTSLENGTH],
     pub nodename: [c_char; UTSLENGTH],
@@ -19,5 +21,7 @@ pub struct utsname {
 
 #[unsafe(no_mangle)]
 pub unsafe extern "C" fn uname(uts: *mut utsname) -> c_int {
-    Sys::uname(uts).map(|()| 0).or_minus_one_errno()
+    Sys::uname(Out::nonnull(uts))
+        .map(|()| 0)
+        .or_minus_one_errno()
 }

src/header/unistd/mod.rs

@@ -563,7 +563,7 @@ pub extern "C" fn gethostid() -> c_long {
 pub unsafe extern "C" fn gethostname(mut name: *mut c_char, mut len: size_t) -> c_int {
     let mut uts = mem::MaybeUninit::<sys_utsname::utsname>::uninit();
     // TODO
-    let err = Sys::uname(uts.as_mut_ptr())
+    let err = Sys::uname(Out::from_uninit_mut(&mut uts))
         .map(|()| 0)
         .or_minus_one_errno();
     if err < 0 {