diff --git a/src/sys/socket/mod.rs b/src/sys/socket/mod.rs
index af66bc4715..5676e0fb52 100644
--- a/src/sys/socket/mod.rs
+++ b/src/sys/socket/mod.rs
@@ -86,32 +86,49 @@ pub enum SockProtocol {
     KextControl = libc::SYSPROTO_CONTROL,
 }
 
-libc_bitflags!{
-    /// Additional socket options
-    pub struct SockFlag: c_int {
-        /// Set non-blocking mode on the new socket
-        #[cfg(any(target_os = "android",
-                  target_os = "dragonfly",
-                  target_os = "freebsd",
-                  target_os = "linux",
-                  target_os = "netbsd",
-                  target_os = "openbsd"))]
-        SOCK_NONBLOCK;
-        /// Set close-on-exec on the new descriptor
-        #[cfg(any(target_os = "android",
-                  target_os = "dragonfly",
-                  target_os = "freebsd",
-                  target_os = "linux",
-                  target_os = "netbsd",
-                  target_os = "openbsd"))]
-        SOCK_CLOEXEC;
-        /// Return `EPIPE` instead of raising `SIGPIPE`
-        #[cfg(target_os = "netbsd")]
-        SOCK_NOSIGPIPE;
-        /// For domains `AF_INET(6)`, only allow `connect(2)`, `sendto(2)`, or `sendmsg(2)`
-        /// to the DNS port (typically 53)
-        #[cfg(target_os = "openbsd")]
-        SOCK_DNS;
+cfg_if! {
+    /*
+      Because `nix` provides a new API that does not conform to
+      POSIX or BSD (or directly Linux), add virtual definitions
+      for macOS and iOS that are backed by their equivalent `fcntl` flags.
+    */
+    if #[cfg(any(target_os = "macos",
+                 target_os = "ios"))] {
+        bitflags! {
+            pub struct SockFlag: c_int {
+                const SOCK_NONBLOCK = libc::O_NONBLOCK;
+                const SOCK_CLOEXEC = libc::O_CLOEXEC;
+            }
+        }
+    } else {
+        libc_bitflags!{
+            /// Additional socket options
+            pub struct SockFlag: c_int {
+                /// Set non-blocking mode on the new socket
+                #[cfg(any(target_os = "android",
+                          target_os = "dragonfly",
+                          target_os = "freebsd",
+                          target_os = "linux",
+                          target_os = "netbsd",
+                          target_os = "openbsd"))]
+                SOCK_NONBLOCK;
+                /// Set close-on-exec on the new descriptor
+                #[cfg(any(target_os = "android",
+                          target_os = "dragonfly",
+                          target_os = "freebsd",
+                          target_os = "linux",
+                          target_os = "netbsd",
+                          target_os = "openbsd"))]
+                SOCK_CLOEXEC;
+                /// Return `EPIPE` instead of raising `SIGPIPE`
+                #[cfg(target_os = "netbsd")]
+                SOCK_NOSIGPIPE;
+                /// For domains `AF_INET(6)`, only allow `connect(2)`, `sendto(2)`, or `sendmsg(2)`
+                /// to the DNS port (typically 53)
+                #[cfg(target_os = "openbsd")]
+                SOCK_DNS;
+            }
+        }
     }
 }
 
@@ -709,7 +726,9 @@ pub fn socket<T: Into<Option<SockProtocol>>>(domain: AddressFamily, ty: SockType
     #[cfg(any(target_os = "android",
               target_os = "dragonfly",
               target_os = "freebsd",
+              target_os = "ios",
               target_os = "linux",
+              target_os = "macos",
               target_os = "netbsd",
               target_os = "openbsd"))]
     {
@@ -754,7 +773,9 @@ pub fn socketpair<T: Into<Option<SockProtocol>>>(domain: AddressFamily, ty: Sock
     #[cfg(any(target_os = "android",
               target_os = "dragonfly",
               target_os = "freebsd",
+              target_os = "ios",
               target_os = "linux",
+              target_os = "macos",
               target_os = "netbsd",
               target_os = "openbsd"))]
     {
@@ -836,7 +857,9 @@ fn accept4_polyfill(sockfd: RawFd, flags: SockFlag) -> Result<RawFd> {
     #[cfg(any(target_os = "android",
               target_os = "dragonfly",
               target_os = "freebsd",
+              target_os = "ios",
               target_os = "linux",
+              target_os = "macos",
               target_os = "netbsd",
               target_os = "openbsd"))]
     {
diff --git a/test/sys/test_socket.rs b/test/sys/test_socket.rs
index a997fbca9e..567ae030b9 100644
--- a/test/sys/test_socket.rs
+++ b/test/sys/test_socket.rs
@@ -255,3 +255,69 @@ pub fn test_syscontrol() {
     // requires root privileges
     // connect(fd, &sockaddr).expect("connect failed");
 }
+
+/// Test non-blocking mode on new sockets via SockFlag::O_NONBLOCK
+#[cfg(any(target_os = "android",
+          target_os = "dragonfly",
+          target_os = "freebsd",
+          target_os = "ios",
+          target_os = "linux",
+          target_os = "macos",
+          target_os = "netbsd",
+          target_os = "openbsd"))]
+#[test]
+pub fn test_sockflag_nonblock() {
+    use libc;
+    use nix::fcntl::{fcntl};
+    use nix::fcntl::FcntlArg::{F_GETFL};
+    use nix::sys::socket::{socket, AddressFamily, SockType, SockFlag};
+
+    /* first, try without SockFlag::SOCK_NONBLOCK */
+    let sock = socket(AddressFamily::Unix, SockType::Stream, SockFlag::empty(), None)
+                 .expect("socket failed");
+
+    let fcntl_res = fcntl(sock, F_GETFL).expect("fcntl failed");
+
+    assert!(fcntl_res & libc::O_NONBLOCK == 0);
+
+    /* next, try with SockFlag::SOCK_NONBLOCK */
+    let sock = socket(AddressFamily::Unix, SockType::Stream, SockFlag::SOCK_NONBLOCK, None)
+                 .expect("socket failed");
+
+    let fcntl_res = fcntl(sock, F_GETFL).expect("fcntl failed");
+
+    assert!(fcntl_res & libc::O_NONBLOCK == libc::O_NONBLOCK);
+}
+
+/// Test close-on-exec on new sockets via SockFlag::SOCK_CLOEXEC
+#[cfg(any(target_os = "android",
+          target_os = "dragonfly",
+          target_os = "freebsd",
+          target_os = "ios",
+          target_os = "linux",
+          target_os = "macos",
+          target_os = "netbsd",
+          target_os = "openbsd"))]
+#[test]
+pub fn test_sockflag_cloexec() {
+    use libc;
+    use nix::fcntl::{fcntl};
+    use nix::fcntl::FcntlArg::{F_GETFD};
+    use nix::sys::socket::{socket, AddressFamily, SockType, SockFlag};
+
+    /* first, test without SockFlag::SOCK_CLOEXEC */
+    let sock = socket(AddressFamily::Unix, SockType::Stream, SockFlag::empty(), None)
+                 .expect("socket failed");
+
+    let fcntl_res = fcntl(sock, F_GETFD).expect("fcntl failed");
+
+    assert!(fcntl_res & libc::FD_CLOEXEC == 0);
+
+    /* next, test without SockFlag::SOCK_CLOEXEC */
+    let sock = socket(AddressFamily::Unix, SockType::Stream, SockFlag::SOCK_CLOEXEC, None)
+                 .expect("socket failed");
+
+    let fcntl_res = fcntl(sock, F_GETFD).expect("fcntl failed");
+
+    assert!(fcntl_res & libc::FD_CLOEXEC == libc::FD_CLOEXEC);
+}