7 files changed, 91 insertions, 0 deletions
diff --git a/src/libstd/sys/unix/ext/net.rs b/src/libstd/sys/unix/ext/net.rs
index 4c3cb67c9ee..60ec73d9de2 100644
--- a/src/libstd/sys/unix/ext/net.rs
+++ b/src/libstd/sys/unix/ext/net.rs
@@ -614,6 +614,11 @@ impl io::Read for UnixStream {
     }
 
     #[inline]
+    fn can_read_vectored(&self) -> bool {
+        io::Read::can_read_vectored(&&*self)
+    }
+
+    #[inline]
     unsafe fn initializer(&self) -> Initializer {
         Initializer::nop()
     }
@@ -630,6 +635,11 @@ impl<'a> io::Read for &'a UnixStream {
     }
 
     #[inline]
+    fn can_read_vectored(&self) -> bool {
+        self.0.can_read_vectored()
+    }
+
+    #[inline]
     unsafe fn initializer(&self) -> Initializer {
         Initializer::nop()
     }
@@ -645,6 +655,11 @@ impl io::Write for UnixStream {
         io::Write::write_vectored(&mut &*self, bufs)
     }
 
+    #[inline]
+    fn can_write_vectored(&self) -> bool {
+        io::Write::can_write_vectored(&&*self)
+    }
+
     fn flush(&mut self) -> io::Result<()> {
         io::Write::flush(&mut &*self)
     }
@@ -660,6 +675,11 @@ impl<'a> io::Write for &'a UnixStream {
         self.0.write_vectored(bufs)
     }
 
+    #[inline]
+    fn can_write_vectored(&self) -> bool {
+        self.0.can_write_vectored()
+    }
+
     fn flush(&mut self) -> io::Result<()> {
         Ok(())
     }
diff --git a/src/libstd/sys/unix/fd.rs b/src/libstd/sys/unix/fd.rs
index 1bba56e334a..7083785f426 100644
--- a/src/libstd/sys/unix/fd.rs
+++ b/src/libstd/sys/unix/fd.rs
@@ -64,6 +64,11 @@ impl FileDesc {
         Ok(ret as usize)
     }
 
+    #[inline]
+    pub fn can_read_vectored(&self) -> bool {
+        true
+    }
+
     pub fn read_to_end(&self, buf: &mut Vec<u8>) -> io::Result<usize> {
         let mut me = self;
         (&mut me).read_to_end(buf)
@@ -116,6 +121,11 @@ impl FileDesc {
         Ok(ret as usize)
     }
 
+    #[inline]
+    pub fn can_write_vectored(&self) -> bool {
+        true
+    }
+
     pub fn write_at(&self, buf: &[u8], offset: u64) -> io::Result<usize> {
         #[cfg(target_os = "android")]
         use super::android::cvt_pwrite64;
diff --git a/src/libstd/sys/unix/fs.rs b/src/libstd/sys/unix/fs.rs
index a233aa47dff..1e8bbd4325b 100644
--- a/src/libstd/sys/unix/fs.rs
+++ b/src/libstd/sys/unix/fs.rs
@@ -828,6 +828,11 @@ impl File {
         self.0.read_vectored(bufs)
     }
 
+    #[inline]
+    pub fn can_read_vectored(&self) -> bool {
+        self.0.can_read_vectored()
+    }
+
     pub fn read_at(&self, buf: &mut [u8], offset: u64) -> io::Result<usize> {
         self.0.read_at(buf, offset)
     }
@@ -840,6 +845,11 @@ impl File {
         self.0.write_vectored(bufs)
     }
 
+    #[inline]
+    pub fn can_write_vectored(&self) -> bool {
+        self.0.can_write_vectored()
+    }
+
     pub fn write_at(&self, buf: &[u8], offset: u64) -> io::Result<usize> {
         self.0.write_at(buf, offset)
     }
diff --git a/src/libstd/sys/unix/l4re.rs b/src/libstd/sys/unix/l4re.rs
index c6e4f5693ed..8510e56af37 100644
--- a/src/libstd/sys/unix/l4re.rs
+++ b/src/libstd/sys/unix/l4re.rs
@@ -55,6 +55,10 @@ pub mod net {
             unimpl!();
         }
 
+        pub fn can_read_vectored(&self) -> bool {
+            unimpl!();
+        }
+
         pub fn peek(&self, _: &mut [u8]) -> io::Result<usize> {
             unimpl!();
         }
@@ -75,6 +79,10 @@ pub mod net {
             unimpl!();
         }
 
+        pub fn can_write_vectored(&self) -> bool {
+            unimpl!();
+        }
+
         pub fn set_timeout(&self, _: Option<Duration>, _: libc::c_int) -> io::Result<()> {
             unimpl!();
         }
@@ -171,6 +179,10 @@ pub mod net {
             unimpl!();
         }
 
+        pub fn can_read_vectored(&self) -> bool {
+            unimpl!();
+        }
+
         pub fn write(&self, _: &[u8]) -> io::Result<usize> {
             unimpl!();
         }
@@ -179,6 +191,10 @@ pub mod net {
             unimpl!();
         }
 
+        pub fn can_write_vectored(&self) -> bool {
+            unimpl!();
+        }
+
         pub fn peer_addr(&self) -> io::Result<SocketAddr> {
             unimpl!();
         }
diff --git a/src/libstd/sys/unix/net.rs b/src/libstd/sys/unix/net.rs
index d18c22b0573..ed97ddf333f 100644
--- a/src/libstd/sys/unix/net.rs
+++ b/src/libstd/sys/unix/net.rs
@@ -226,6 +226,11 @@ impl Socket {
         self.0.read_vectored(bufs)
     }
 
+    #[inline]
+    pub fn can_read_vectored(&self) -> bool {
+        self.0.can_read_vectored()
+    }
+
     fn recv_from_with_flags(
         &self,
         buf: &mut [u8],
@@ -263,6 +268,11 @@ impl Socket {
         self.0.write_vectored(bufs)
     }
 
+    #[inline]
+    pub fn can_write_vectored(&self) -> bool {
+        self.0.can_write_vectored()
+    }
+
     pub fn set_timeout(&self, dur: Option<Duration>, kind: libc::c_int) -> io::Result<()> {
         let timeout = match dur {
             Some(dur) => {
diff --git a/src/libstd/sys/unix/pipe.rs b/src/libstd/sys/unix/pipe.rs
index 2a861c87801..d8ac36df9ec 100644
--- a/src/libstd/sys/unix/pipe.rs
+++ b/src/libstd/sys/unix/pipe.rs
@@ -64,6 +64,11 @@ impl AnonPipe {
         self.0.read_vectored(bufs)
     }
 
+    #[inline]
+    pub fn can_read_vectored(&self) -> bool {
+        self.0.can_read_vectored()
+    }
+
     pub fn write(&self, buf: &[u8]) -> io::Result<usize> {
         self.0.write(buf)
     }
@@ -72,6 +77,11 @@ impl AnonPipe {
         self.0.write_vectored(bufs)
     }
 
+    #[inline]
+    pub fn can_write_vectored(&self) -> bool {
+        self.0.can_write_vectored()
+    }
+
     pub fn fd(&self) -> &FileDesc {
         &self.0
     }
diff --git a/src/libstd/sys/unix/stdio.rs b/src/libstd/sys/unix/stdio.rs
index b9c56963885..4026dd4e497 100644
--- a/src/libstd/sys/unix/stdio.rs
+++ b/src/libstd/sys/unix/stdio.rs
@@ -20,6 +20,11 @@ impl io::Read for Stdin {
     fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> io::Result<usize> {
         ManuallyDrop::new(FileDesc::new(libc::STDIN_FILENO)).read_vectored(bufs)
     }
+
+    #[inline]
+    fn can_read_vectored(&self) -> bool {
+        true
+    }
 }
 
 impl Stdout {
@@ -37,6 +42,11 @@ impl io::Write for Stdout {
         ManuallyDrop::new(FileDesc::new(libc::STDOUT_FILENO)).write_vectored(bufs)
     }
 
+    #[inline]
+    fn can_write_vectored(&self) -> bool {
+        true
+    }
+
     fn flush(&mut self) -> io::Result<()> {
         Ok(())
     }
@@ -57,6 +67,11 @@ impl io::Write for Stderr {
         ManuallyDrop::new(FileDesc::new(libc::STDERR_FILENO)).write_vectored(bufs)
     }
 
+    #[inline]
+    fn can_write_vectored(&self) -> bool {
+        true
+    }
+
     fn flush(&mut self) -> io::Result<()> {
         Ok(())
     }