diff --git a/src/unix/bsd/apple/mod.rs b/src/unix/bsd/apple/mod.rs
index 72e6deaba4bb3f03d93c004be30486fbef669246..aa4d1ac74575e9f96fac8ec3313765ce54b243a1 100644
--- a/src/unix/bsd/apple/mod.rs
+++ b/src/unix/bsd/apple/mod.rs
@@ -621,6 +621,8 @@ pub const EOWNERDEAD: ::c_int = 105;
 pub const EQFULL: ::c_int = 106;
 pub const ELAST: ::c_int = 106;
 
+pub const EAI_SYSTEM: ::c_int = 11;
+
 pub const F_DUPFD: ::c_int = 0;
 pub const F_DUPFD_CLOEXEC: ::c_int = 67;
 pub const F_GETFD: ::c_int = 1;
diff --git a/src/unix/bsd/freebsdlike/mod.rs b/src/unix/bsd/freebsdlike/mod.rs
index 9cfdf6e08454cbbaecca89deb9f5967582bc1f66..3f040c05f3491868a0f5dbdc8dbf9a94928422c0 100644
--- a/src/unix/bsd/freebsdlike/mod.rs
+++ b/src/unix/bsd/freebsdlike/mod.rs
@@ -467,6 +467,8 @@ pub const EMULTIHOP: ::c_int = 90;
 pub const ENOLINK: ::c_int = 91;
 pub const EPROTO: ::c_int = 92;
 
+pub const EAI_SYSTEM: ::c_int = 11;
+
 pub const F_DUPFD: ::c_int = 0;
 pub const F_GETFD: ::c_int = 1;
 pub const F_SETFD: ::c_int = 2;
diff --git a/src/unix/bsd/netbsdlike/netbsd.rs b/src/unix/bsd/netbsdlike/netbsd.rs
index 6edfb08d5ec1e7452a9938d77ea27c303909e3b3..c4e711db8336017e16f6d6e4dbfcdff107ff774d 100644
--- a/src/unix/bsd/netbsdlike/netbsd.rs
+++ b/src/unix/bsd/netbsdlike/netbsd.rs
@@ -547,6 +547,8 @@ pub const KERN_PROC_RUID: ::c_int = 6;
 pub const KERN_PROC_GID: ::c_int = 7;
 pub const KERN_PROC_RGID: ::c_int = 8;
 
+pub const EAI_SYSTEM: ::c_int = 11;
+
 extern {
     pub fn lutimes(file: *const ::c_char, times: *const ::timeval) -> ::c_int;
     pub fn getnameinfo(sa: *const ::sockaddr,
diff --git a/src/unix/bsd/netbsdlike/openbsdlike/mod.rs b/src/unix/bsd/netbsdlike/openbsdlike/mod.rs
index 03ed1948d085876c47ffb1287db7634f049bb657..4d35822fbe27ff88a53dff51599dda387ccd22a3 100644
--- a/src/unix/bsd/netbsdlike/openbsdlike/mod.rs
+++ b/src/unix/bsd/netbsdlike/openbsdlike/mod.rs
@@ -172,6 +172,8 @@ pub const EIPSEC : ::c_int = 82;
 pub const ENOMEDIUM : ::c_int = 85;
 pub const EMEDIUMTYPE : ::c_int = 86;
 
+pub const EAI_SYSTEM: ::c_int = -11;
+
 pub const RUSAGE_THREAD: ::c_int = 1;
 
 pub const MAP_COPY : ::c_int = 0x0002;
diff --git a/src/unix/notbsd/android/mod.rs b/src/unix/notbsd/android/mod.rs
index 27ffbd7ebe8763c690e386c940650c15c583cd7b..efc136817db6f1c4d95112d86dab07eae2798d6e 100644
--- a/src/unix/notbsd/android/mod.rs
+++ b/src/unix/notbsd/android/mod.rs
@@ -580,6 +580,8 @@ pub const ICANON: ::tcflag_t = 0x00000002;
 pub const PENDIN: ::tcflag_t = 0x00004000;
 pub const NOFLSH: ::tcflag_t = 0x00000080;
 
+pub const EAI_SYSTEM: ::c_int = 11;
+
 pub const NETLINK_ROUTE: ::c_int = 0;
 pub const NETLINK_UNUSED: ::c_int = 1;
 pub const NETLINK_USERSOCK: ::c_int = 2;
diff --git a/src/unix/notbsd/linux/mod.rs b/src/unix/notbsd/linux/mod.rs
index 000773f97e0365f73987c2262f8f81e155225dba..6aea83aaeba3182b27aa34f114f508369eff0377 100644
--- a/src/unix/notbsd/linux/mod.rs
+++ b/src/unix/notbsd/linux/mod.rs
@@ -504,6 +504,8 @@ pub const SYNC_FILE_RANGE_WAIT_BEFORE: ::c_uint = 1;
 pub const SYNC_FILE_RANGE_WRITE: ::c_uint = 2;
 pub const SYNC_FILE_RANGE_WAIT_AFTER: ::c_uint = 4;
 
+pub const EAI_SYSTEM: ::c_int = -11;
+
 f! {
     pub fn CPU_ZERO(cpuset: &mut cpu_set_t) -> () {
         for slot in cpuset.bits.iter_mut() {
diff --git a/src/unix/solaris/mod.rs b/src/unix/solaris/mod.rs
index 31f67b78e628176c005e5549c32afe33bb4e9671..e9304d5ee4f2ea84c0db5755f0fafafc8dff1595 100644
--- a/src/unix/solaris/mod.rs
+++ b/src/unix/solaris/mod.rs
@@ -651,6 +651,8 @@ pub const EMULTIHOP: ::c_int = 74;
 pub const ENOLINK: ::c_int = 67;
 pub const EPROTO: ::c_int = 71;
 
+pub const EAI_SYSTEM: ::cc_int = 11;
+
 pub const F_DUPFD: ::c_int = 0;
 pub const F_GETFD: ::c_int = 1;
 pub const F_SETFD: ::c_int = 2;