Add WIFCONTINUED for NetBSD and OpenBSD

Author: Susurrus

src/unix/bsd/netbsdlike/netbsd/mod.rs

@@ -743,6 +743,10 @@ f! {
     pub fn dirfd(dirp: *mut ::DIR) -> ::c_int {
         unsafe { *(dirp as *const ::c_int) }
     }
+
+    pub fn WIFCONTINUED(status: ::c_int) -> bool {
+        status == 0xffff
+    }
 }
 
 extern {

src/unix/bsd/netbsdlike/openbsdlike/mod.rs

@@ -583,6 +583,12 @@ pub const SOCK_CLOEXEC: ::c_int = 0x8000;
 pub const SOCK_NONBLOCK: ::c_int = 0x4000;
 pub const SOCK_DNS: ::c_int = 0x1000;
 
+f! {
+    pub fn WIFCONTINUED(status: ::c_int) -> bool {
+        status & 0o177777 == 0o177777
+    }
+}
+
 extern {
     pub fn dirfd(dirp: *mut ::DIR) -> ::c_int;
     pub fn getnameinfo(sa: *const ::sockaddr,