diff --git a/src/fuchsia/mod.rs b/src/fuchsia/mod.rs
index deb1c5d95f765cb7dcf042eaa8028e0fab0869fb..e785fabf8eae55af132b6c224554c0bd05f59d5a 100644
--- a/src/fuchsia/mod.rs
+++ b/src/fuchsia/mod.rs
@@ -3285,6 +3285,7 @@ extern {
                 -> ::ssize_t;
     pub fn rmdir(path: *const c_char) -> ::c_int;
     pub fn seteuid(uid: uid_t) -> ::c_int;
+    pub fn setegid(gid: gid_t) -> ::c_int;
     pub fn setgid(gid: gid_t) -> ::c_int;
     pub fn setpgid(pid: pid_t, pgid: pid_t) -> ::c_int;
     pub fn setsid() -> pid_t;
diff --git a/src/unix/mod.rs b/src/unix/mod.rs
index 1358976a53a1817b0d9d724d55ec79be46233e5d..370d7f48cba754403221c180cff2223666e88299 100644
--- a/src/unix/mod.rs
+++ b/src/unix/mod.rs
@@ -711,6 +711,7 @@ extern {
                 -> ::ssize_t;
     pub fn rmdir(path: *const c_char) -> ::c_int;
     pub fn seteuid(uid: uid_t) -> ::c_int;
+    pub fn setegid(gid: gid_t) -> ::c_int;
     pub fn setgid(gid: gid_t) -> ::c_int;
     pub fn setpgid(pid: pid_t, pgid: pid_t) -> ::c_int;
     pub fn setsid() -> pid_t;