re-add pipe::read impl to libst2.

src/libst2/sys/unix/pipe.rs

@@ -73,7 +73,18 @@ impl UnixStream {
     #[cfg(not(target_os = "linux"))]
     fn lock_nonblocking<'a>(&'a self) -> Guard<'a> { unimplemented!() }
 
-    pub fn read(&mut self, buf: &mut [u8]) -> IoResult<uint> { unimplemented!() }
+    pub fn read(&mut self, buf: &mut [u8]) -> IoResult<uint> {
+        let fd = self.fd();
+        let dolock = || self.lock_nonblocking();
+        let doread = |nb| unsafe {
+            let flags = if nb {c::MSG_DONTWAIT} else {0};
+            libc::recv(fd,
+                       buf.as_mut_ptr() as *mut libc::c_void,
+                       buf.len() as libc::size_t,
+                       flags) as libc::c_int
+        };
+        read(fd, self.read_deadline, dolock, doread)
+    }
 
     pub fn write(&mut self, buf: &[u8]) -> IoResult<()> { unimplemented!() }