diff --git a/src/unix/newlib/arm/mod.rs b/src/unix/newlib/arm/mod.rs
index 9b5978fc538c3..147d08d34187a 100644
--- a/src/unix/newlib/arm/mod.rs
+++ b/src/unix/newlib/arm/mod.rs
@@ -4,11 +4,13 @@ pub type clock_t = c_long;
 pub type wchar_t = u32;
 
 s! {
+    #[cfg(not(target_os = "rtems"))]
     pub struct sockaddr {
         pub sa_family: crate::sa_family_t,
         pub sa_data: [c_char; 14],
     }
 
+    #[cfg(not(target_os = "rtems"))]
     pub struct sockaddr_in6 {
         pub sin6_family: crate::sa_family_t,
         pub sin6_port: crate::in_port_t,
@@ -17,6 +19,7 @@ s! {
         pub sin6_scope_id: u32,
     }
 
+    #[cfg(not(target_os = "rtems"))]
     pub struct sockaddr_in {
         pub sin_family: crate::sa_family_t,
         pub sin_port: crate::in_port_t,
@@ -24,31 +27,48 @@ s! {
         pub sin_zero: [u8; 8],
     }
 
+    #[cfg(not(target_os = "rtems"))]
     pub struct sockaddr_storage {
         pub ss_family: crate::sa_family_t,
         __ss_padding: Padding<[u8; 26]>,
     }
 }
 
+#[cfg(not(target_os = "rtems"))]
 pub const AF_INET6: c_int = 23;
 
+#[cfg(not(target_os = "rtems"))]
 pub const FIONBIO: c_ulong = 1;
 
+#[cfg(not(target_os = "rtems"))]
 pub const POLLIN: c_short = 0x1;
+#[cfg(not(target_os = "rtems"))]
 pub const POLLPRI: c_short = 0x2;
+#[cfg(not(target_os = "rtems"))]
 pub const POLLHUP: c_short = 0x4;
+#[cfg(not(target_os = "rtems"))]
 pub const POLLERR: c_short = 0x8;
+#[cfg(not(target_os = "rtems"))]
 pub const POLLOUT: c_short = 0x10;
+#[cfg(not(target_os = "rtems"))]
 pub const POLLNVAL: c_short = 0x20;
 
+#[cfg(not(target_os = "rtems"))]
 pub const SOL_SOCKET: c_int = 65535;
 
+#[cfg(not(target_os = "rtems"))]
 pub const MSG_OOB: c_int = 1;
+#[cfg(not(target_os = "rtems"))]
 pub const MSG_PEEK: c_int = 2;
+#[cfg(not(target_os = "rtems"))]
 pub const MSG_DONTWAIT: c_int = 4;
+#[cfg(not(target_os = "rtems"))]
 pub const MSG_DONTROUTE: c_int = 0;
+#[cfg(not(target_os = "rtems"))]
 pub const MSG_WAITALL: c_int = 0;
+#[cfg(not(target_os = "rtems"))]
 pub const MSG_MORE: c_int = 0;
+#[cfg(not(target_os = "rtems"))]
 pub const MSG_NOSIGNAL: c_int = 0;
 
 pub use crate::unix::newlib::generic::{
diff --git a/src/unix/newlib/mod.rs b/src/unix/newlib/mod.rs
index ee6abccedfb6a..6ec4be3d0ab7a 100644
--- a/src/unix/newlib/mod.rs
+++ b/src/unix/newlib/mod.rs
@@ -340,6 +340,8 @@ pub const PTHREAD_RWLOCK_INITIALIZER: pthread_rwlock_t = pthread_rwlock_t {
 cfg_if! {
     if #[cfg(target_os = "espidf")] {
         pub const NCCS: usize = 11;
+    } else if #[cfg(target_os = "rtems")] {
+        pub const NCCS: usize = 20;
     } else {
         pub const NCCS: usize = 32;
     }
@@ -399,7 +401,7 @@ pub const PTHREAD_MUTEX_ERRORCHECK: c_int = 2;
 cfg_if! {
     if #[cfg(any(target_os = "horizon", target_os = "espidf"))] {
         pub const FD_SETSIZE: c_int = 64;
-    } else if #[cfg(target_os = "vita")] {
+    } else if #[cfg(any(target_os = "vita", target_os = "rtems"))] {
         pub const FD_SETSIZE: c_int = 256;
     } else {
         pub const FD_SETSIZE: c_int = 1024;
@@ -531,7 +533,7 @@ pub const O_NONBLOCK: c_int = 16384;
 
 pub const O_ACCMODE: c_int = 3;
 cfg_if! {
-    if #[cfg(target_os = "espidf")] {
+    if #[cfg(any(target_os = "espidf", target_os = "rtems"))] {
         pub const O_CLOEXEC: c_int = 0x40000;
     } else {
         pub const O_CLOEXEC: c_int = 0x80000;
@@ -577,6 +579,8 @@ pub const PF_INET: c_int = 2;
 cfg_if! {
     if #[cfg(target_os = "espidf")] {
         pub const PF_INET6: c_int = 10;
+    } else if #[cfg(target_os = "rtems")] {
+        pub const PF_INET6: c_int = 28;
     } else {
         pub const PF_INET6: c_int = 23;
     }
@@ -638,7 +642,13 @@ cfg_if! {
 }
 pub const SO_TYPE: c_int = 0x1008;
 
-pub const SOCK_CLOEXEC: c_int = O_CLOEXEC;
+cfg_if! {
+    if #[cfg(target_os = "rtems")] {
+        pub const SOCK_CLOEXEC: c_int = 0x10000000;
+    } else {
+        pub const SOCK_CLOEXEC: c_int = O_CLOEXEC;
+    }
+}
 
 pub const INET_ADDRSTRLEN: c_int = 16;
 
@@ -662,7 +672,7 @@ pub const IFF_ALTPHYS: c_int = IFF_LINK2; // use alternate physical connection
 pub const IFF_MULTICAST: c_int = 0x8000; // supports multicast
 
 cfg_if! {
-    if #[cfg(target_os = "vita")] {
+    if #[cfg(any(target_os = "vita", target_os = "rtems"))] {
         pub const TCP_NODELAY: c_int = 1;
         pub const TCP_MAXSEG: c_int = 2;
     } else if #[cfg(target_os = "espidf")] {
@@ -698,7 +708,7 @@ cfg_if! {
     }
 }
 cfg_if! {
-    if #[cfg(target_os = "vita")] {
+    if #[cfg(any(target_os = "vita", target_os = "rtems"))] {
         pub const IP_TTL: c_int = 4;
     } else if #[cfg(target_os = "espidf")] {
         pub const IP_TTL: c_int = 2;
@@ -720,7 +730,7 @@ cfg_if! {
 }
 
 cfg_if! {
-    if #[cfg(target_os = "vita")] {
+    if #[cfg(any(target_os = "vita", target_os = "rtems"))] {
         pub const IP_ADD_MEMBERSHIP: c_int = 12;
         pub const IP_DROP_MEMBERSHIP: c_int = 13;
     } else if #[cfg(target_os = "espidf")] {
@@ -755,6 +765,11 @@ cfg_if! {
         pub const NO_DATA: c_int = 211;
         pub const NO_RECOVERY: c_int = 212;
         pub const TRY_AGAIN: c_int = 213;
+    } else if #[cfg(target_os = "rtems")] {
+        pub const HOST_NOT_FOUND: c_int = 1;
+        pub const TRY_AGAIN: c_int = 2;
+        pub const NO_RECOVERY: c_int = 3;
+        pub const NO_DATA: c_int = 4;
     } else {
         pub const HOST_NOT_FOUND: c_int = 1;
         pub const NO_DATA: c_int = 2;
@@ -762,7 +777,13 @@ cfg_if! {
         pub const TRY_AGAIN: c_int = 4;
     }
 }
-pub const NO_ADDRESS: c_int = 2;
+cfg_if! {
+    if #[cfg(target_os = "rtems")] {
+        pub const NO_ADDRESS: c_int = NO_DATA;
+    } else {
+        pub const NO_ADDRESS: c_int = 2;
+    }
+}
 
 pub const AI_PASSIVE: c_int = 1;
 pub const AI_CANONNAME: c_int = 2;
@@ -771,6 +792,9 @@ cfg_if! {
     if #[cfg(target_os = "espidf")] {
         pub const AI_NUMERICSERV: c_int = 8;
         pub const AI_ADDRCONFIG: c_int = 64;
+    } else if #[cfg(target_os = "rtems")] {
+        pub const AI_NUMERICSERV: c_int = 0x00000008;
+        pub const AI_ADDRCONFIG: c_int = 0x00000400;
     } else {
         pub const AI_NUMERICSERV: c_int = 0;
         pub const AI_ADDRCONFIG: c_int = 0;
@@ -783,7 +807,7 @@ pub const NI_NOFQDN: c_int = 1;
 pub const NI_NUMERICHOST: c_int = 2;
 pub const NI_NAMEREQD: c_int = 4;
 cfg_if! {
-    if #[cfg(target_os = "espidf")] {
+    if #[cfg(any(target_os = "espidf", target_os = "rtems"))] {
         pub const NI_NUMERICSERV: c_int = 8;
         pub const NI_DGRAM: c_int = 16;
     } else {
@@ -799,6 +823,11 @@ cfg_if! {
         pub const EAI_MEMORY: c_int = 203;
         pub const EAI_NONAME: c_int = 200;
         pub const EAI_SOCKTYPE: c_int = 10;
+    } else if #[cfg(target_os = "rtems")] {
+        pub const EAI_FAMILY: c_int = 5;
+        pub const EAI_MEMORY: c_int = 6;
+        pub const EAI_NONAME: c_int = 8;
+        pub const EAI_SOCKTYPE: c_int = 10;
     } else if #[cfg(not(target_os = "vita"))] {
         pub const EAI_FAMILY: c_int = -303;
         pub const EAI_MEMORY: c_int = -304;
diff --git a/src/unix/newlib/rtems/mod.rs b/src/unix/newlib/rtems/mod.rs
index fca95f0e95e3e..6bfe435f66626 100644
--- a/src/unix/newlib/rtems/mod.rs
+++ b/src/unix/newlib/rtems/mod.rs
@@ -3,13 +3,65 @@
 use crate::prelude::*;
 
 s! {
+    pub struct sockaddr {
+        pub sa_len: u8,
+        pub sa_family: crate::sa_family_t,
+        pub sa_data: [c_char; 14],
+    }
+
+    pub struct sockaddr_in {
+        pub sin_len: u8,
+        pub sin_family: crate::sa_family_t,
+        pub sin_port: crate::in_port_t,
+        pub sin_addr: crate::in_addr,
+        pub sin_zero: [c_char; 8],
+    }
+
+    pub struct sockaddr_in6 {
+        pub sin6_len: u8,
+        pub sin6_family: crate::sa_family_t,
+        pub sin6_port: crate::in_port_t,
+        pub sin6_flowinfo: u32,
+        pub sin6_addr: crate::in6_addr,
+        pub sin6_scope_id: u32,
+    }
+
     pub struct sockaddr_un {
+        pub sun_len: u8,
         pub sun_family: crate::sa_family_t,
-        pub sun_path: [c_char; 108usize],
+        pub sun_path: [c_char; 104usize],
+    }
+
+    pub struct sockaddr_storage {
+        pub ss_len: u8,
+        pub ss_family: crate::sa_family_t,
+        __ss_pad1: Padding<[u8; 6]>,
+        __ss_align: i64,
+        __ss_pad2: Padding<[u8; 112]>,
     }
 }
 
 pub const AF_UNIX: c_int = 1;
+pub const AF_INET6: c_int = 28;
+
+pub const FIONBIO: c_ulong = 0x8004667e;
+
+pub const POLLIN: c_short = 0x0001;
+pub const POLLPRI: c_short = 0x0002;
+pub const POLLOUT: c_short = 0x0004;
+pub const POLLERR: c_short = 0x0008;
+pub const POLLHUP: c_short = 0x0010;
+pub const POLLNVAL: c_short = 0x0020;
+
+pub const SOL_SOCKET: c_int = 0xffff;
+
+pub const MSG_OOB: c_int = 0x1;
+pub const MSG_PEEK: c_int = 0x2;
+pub const MSG_DONTROUTE: c_int = 0x4;
+pub const MSG_WAITALL: c_int = 0x40;
+pub const MSG_DONTWAIT: c_int = 0x80;
+pub const MSG_NOSIGNAL: c_int = 0x20000;
+pub const MSG_MORE: c_int = 0;
 
 pub const RTLD_DEFAULT: *mut c_void = -2isize as *mut c_void;