Enable pwritev and preadv for more operating systems.

Author: asomers

CHANGELOG.md

@@ -32,6 +32,8 @@ This project adheres to [Semantic Versioning](https://semver.org/).
   (#[1447](https://github.com/nix-rust/nix/pull/1447))
 - Added `TcpRepair`
   (#[1503](https://github.com/nix-rust/nix/pull/1503))
+- Enabled `pwritev` and `preadv` for more operating systems.
+  (#[1511](https://github.com/nix-rust/nix/pull/1511))
 
 ### Changed
 

Cargo.toml

@@ -25,7 +25,7 @@ targets = [
 ]
 
 [dependencies]
-libc = { git = "https://github.com/rust-lang/libc", rev = "f5e31f208", features = [ "extra_traits" ] }
+libc = { git = "https://github.com/rust-lang/libc", rev = "621a95373", features = [ "extra_traits" ] }
 bitflags = "1.3.1"
 cfg-if = "1.0"
 

src/sys/uio.rs

@@ -30,11 +30,7 @@ pub fn readv(fd: RawFd, iov: &mut [IoVec<&mut [u8]>]) -> Result<usize> {
 /// or an error occurs. The file offset is not changed.
 ///
 /// See also: [`writev`](fn.writev.html) and [`pwrite`](fn.pwrite.html)
-#[cfg(any(target_os = "dragonfly",
-          target_os = "freebsd",
-          target_os = "linux",
-          target_os = "netbsd",
-          target_os = "openbsd"))]
+#[cfg(not(target_os = "redox"))]
 pub fn pwritev(fd: RawFd, iov: &[IoVec<&[u8]>],
                offset: off_t) -> Result<usize> {
     let res = unsafe {
@@ -51,11 +47,7 @@ pub fn pwritev(fd: RawFd, iov: &[IoVec<&[u8]>],
 /// changed.
 ///
 /// See also: [`readv`](fn.readv.html) and [`pread`](fn.pread.html)
-#[cfg(any(target_os = "dragonfly",
-          target_os = "freebsd",
-          target_os = "linux",
-          target_os = "netbsd",
-          target_os = "openbsd"))]
+#[cfg(not(target_os = "redox"))]
 pub fn preadv(fd: RawFd, iov: &[IoVec<&mut [u8]>],
               offset: off_t) -> Result<usize> {
     let res = unsafe {
@@ -181,7 +173,7 @@ pub fn process_vm_readv(
 
 /// A vector of buffers.
 ///
-/// Vectored I/O methods like [`pwritev`] and [`preadv`] use this structure for
+/// Vectored I/O methods like [`writev`] and [`readv`] use this structure for
 /// both reading and writing.  Each `IoVec` specifies the base address and
 /// length of an area in memory.
 #[repr(transparent)]