diff --git a/src/unix/redox/mod.rs b/src/unix/redox/mod.rs
index 7870eb7f1ad46..02beda431277e 100644
--- a/src/unix/redox/mod.rs
+++ b/src/unix/redox/mod.rs
@@ -375,6 +375,7 @@ pub const EPROTONOSUPPORT: ::c_int = 93; /* Protocol not supported */
 pub const ESOCKTNOSUPPORT: ::c_int = 94; /* Socket type not supported */
 /* Operation not supported on transport endpoint */
 pub const EOPNOTSUPP: ::c_int = 95;
+pub const ENOTSUP: ::c_int = EOPNOTSUPP;
 pub const EPFNOSUPPORT: ::c_int = 96; /* Protocol family not supported */
 /* Address family not supported by protocol */
 pub const EAFNOSUPPORT: ::c_int = 97;