diff --git a/src/unix/bsd/freebsdlike/mod.rs b/src/unix/bsd/freebsdlike/mod.rs
index 875aa8f8ff100..7cce72a0b3ee0 100644
--- a/src/unix/bsd/freebsdlike/mod.rs
+++ b/src/unix/bsd/freebsdlike/mod.rs
@@ -907,6 +907,7 @@ extern {
                          abstime: *const ::timespec) -> ::c_int;
     pub fn pthread_mutex_timedlock(lock: *mut pthread_mutex_t,
                                    abstime: *const ::timespec) -> ::c_int;
+    pub fn pipe2(fds: *mut ::c_int, flags: ::c_int) -> ::c_int;
 }
 
 cfg_if! {
diff --git a/src/unix/bsd/netbsdlike/mod.rs b/src/unix/bsd/netbsdlike/mod.rs
index e8c82883d2bb0..2818c3aedcc36 100644
--- a/src/unix/bsd/netbsdlike/mod.rs
+++ b/src/unix/bsd/netbsdlike/mod.rs
@@ -535,6 +535,7 @@ extern {
     pub fn sethostname(name: *const ::c_char, len: ::size_t) -> ::c_int;
     pub fn pthread_mutex_timedlock(lock: *mut pthread_mutex_t,
                                    abstime: *const ::timespec) -> ::c_int;
+    pub fn pipe2(fds: *mut ::c_int, flags: ::c_int) -> ::c_int;
 }
 
 cfg_if! {