diff --git a/src/unix/mod.rs b/src/unix/mod.rs
index 648a7aa6fe836..39822544c15cf 100644
--- a/src/unix/mod.rs
+++ b/src/unix/mod.rs
@@ -133,8 +133,6 @@ pub const DT_REG: u8 = 8;
 pub const DT_LNK: u8 = 10;
 pub const DT_SOCK: u8 = 12;
 
-pub const FD_CLOEXEC: ::c_int = 0x1;
-
 pub const USRQUOTA: ::c_int = 0;
 pub const GRPQUOTA: ::c_int = 1;
 
@@ -198,6 +196,9 @@ pub const PRIO_USER: ::c_int = 2;
 pub const PRIO_MIN: ::c_int = -20;
 pub const PRIO_MAX: ::c_int = 20;
 
+/* Header <fcntl.h> */
+pub const FD_CLOEXEC: ::c_int = 0x1;
+
 cfg_if! {
     if #[cfg(dox)] {
         // on dox builds don't pull in anything
@@ -318,16 +319,6 @@ extern {
     pub fn fdopen(fd: ::c_int, mode: *const c_char) -> *mut ::FILE;
     pub fn fileno(stream: *mut ::FILE) -> ::c_int;
 
-    #[cfg_attr(all(target_os = "macos", target_arch = "x86"),
-               link_name = "open$UNIX2003")]
-    pub fn open(path: *const c_char, oflag: ::c_int, ...) -> ::c_int;
-    #[cfg_attr(all(target_os = "macos", target_arch = "x86"),
-               link_name = "creat$UNIX2003")]
-    pub fn creat(path: *const c_char, mode: mode_t) -> ::c_int;
-    #[cfg_attr(all(target_os = "macos", target_arch = "x86"),
-               link_name = "fcntl$UNIX2003")]
-    pub fn fcntl(fd: ::c_int, cmd: ::c_int, ...) -> ::c_int;
-
     #[cfg_attr(all(target_os = "macos", target_arch = "x86_64"),
                link_name = "opendir$INODE64")]
     #[cfg_attr(all(target_os = "macos", target_arch = "x86"),
@@ -715,6 +706,17 @@ extern {
                     pshared: ::c_int,
                     value: ::c_uint)
                     -> ::c_int;
+
+    /* Header <fcntl.h> */
+    #[cfg_attr(all(target_os = "macos", target_arch = "x86"),
+               link_name = "creat$UNIX2003")]
+    pub fn creat(path: *const c_char, mode: mode_t) -> ::c_int;
+    #[cfg_attr(all(target_os = "macos", target_arch = "x86"),
+               link_name = "fcntl$UNIX2003")]
+    pub fn fcntl(fd: ::c_int, cmd: ::c_int, ...) -> ::c_int;
+    #[cfg_attr(all(target_os = "macos", target_arch = "x86"),
+               link_name = "open$UNIX2003")]
+    pub fn open(path: *const c_char, oflag: ::c_int, ...) -> ::c_int;
 }
 
 // TODO: get rid of this cfg(not(...))
diff --git a/src/unix/notbsd/android/mod.rs b/src/unix/notbsd/android/mod.rs
index 11013312b7a2d..a8e8bd1682bdb 100644
--- a/src/unix/notbsd/android/mod.rs
+++ b/src/unix/notbsd/android/mod.rs
@@ -578,6 +578,11 @@ pub const ICANON: ::tcflag_t = 0x00000002;
 pub const PENDIN: ::tcflag_t = 0x00004000;
 pub const NOFLSH: ::tcflag_t = 0x00000080;
 
+pub const LOCK_SH: ::c_int = 0x1;
+pub const LOCK_EX: ::c_int = 0x2;
+pub const LOCK_NB: ::c_int = 0x4;
+pub const LOCK_UN: ::c_int = 0x8;
+
 f! {
     pub fn sigemptyset(set: *mut sigset_t) -> ::c_int {
         *set = 0;
diff --git a/src/unix/notbsd/linux/common/b32/arm.rs b/src/unix/notbsd/linux/common/b32/arm.rs
new file mode 100644
index 0000000000000..7af4a4256f5ae
--- /dev/null
+++ b/src/unix/notbsd/linux/common/b32/arm.rs
@@ -0,0 +1,60 @@
+// Native C types
+pub type c_char = u8;
+
+/* Header <fcntl.h> */
+cfg_if! {
+    if #[cfg(any(feature = "file_offset64", target_env = "musl"))] {
+        type flock = ::flock64;
+    } else {
+        s! {
+            pub struct flock {
+                pub l_type: ::c_short,
+                pub l_whence: ::c_short,
+                pub l_start: ::off_t,
+                pub l_len: ::off_t,
+                pub l_pid: ::pid_t,
+            }
+        }
+    }
+}
+
+/* Header <fcntl.h> */
+cfg_if! {
+    if #[cfg(not(any(feature = "file_offset64", target_env = "musl")))] {
+        pub const F_GETLK: ::c_int = 5;
+        pub const F_SETLK: ::c_int = 6;
+        pub const F_SETLKW: ::c_int = 7;
+    } else {
+
+    }
+}
+pub const F_GETOWN: ::c_int = 9;
+pub const F_SETOWN: ::c_int = 8;
+
+pub const F_GETLK64: ::c_int = 12;
+pub const F_SETLK64: ::c_int = 13;
+pub const F_SETLKW64: ::c_int = 14;
+
+// O_CLOEXEC is defined in notbsd/mod.rs
+pub const O_CREAT: ::c_int = 0x40;
+pub const O_DIRECTORY: ::c_int = 0x4000;
+pub const O_EXCL: ::c_int = 0x80;
+pub const O_NOCTTY: ::c_int = 0x100;
+pub const O_NOFOLLOW: ::c_int = 0x8000;
+// O_TRUNC is defined in notbsd/mod.rs
+
+pub const O_APPEND: ::c_int = 0x400;
+pub const O_DSYNC: ::c_int = 0x1000;
+pub const O_NONBLOCK: ::c_int = 0x800;
+pub const O_RSYNC: ::c_int = 0x101000;
+pub const O_SYNC: ::c_int = 0x101000;
+
+// Here start non POSIX definitions.
+pub const O_ASYNC: ::c_int = 0x2000;
+pub const O_DIRECT: ::c_int = 0x10000;
+pub const O_LARGEFILE: ::c_int = 0x20000;
+pub const O_NOATIME: ::c_int = 0x40000;
+pub const O_PATH: ::c_int = 0x200000;
+pub const O_TMPFILE: ::c_int = 0x404000;
+pub const O_NDELAY: ::c_int = ::O_NONBLOCK;
+
diff --git a/src/unix/notbsd/linux/common/b32/mips.rs b/src/unix/notbsd/linux/common/b32/mips.rs
new file mode 100644
index 0000000000000..6a9116adb4a37
--- /dev/null
+++ b/src/unix/notbsd/linux/common/b32/mips.rs
@@ -0,0 +1,61 @@
+// Native C types
+pub type c_char = i8;
+
+/* Header <fcntl.h> */
+cfg_if! {
+    if #[cfg(any(feature = "file_offset64", target_env = "musl"))] {
+        type flock = ::flock64;
+    } else {
+        s! {
+            pub struct flock {
+                pub l_type: ::c_short,
+                pub l_whence: ::c_short,
+                pub l_start: ::off_t,
+                pub l_len: ::off_t,
+                pub l_sysid: ::c_long,
+                pub l_pid: ::pid_t,
+                pad: [::c_long; 4],
+            }
+        }
+    }
+}
+
+/* Header <fcntl.h> */
+cfg_if! {
+    if #[cfg(not(any(feature = "file_offset64", target_env = "musl")))] {
+        pub const F_GETLK: ::c_int = 14;
+        pub const F_SETLK: ::c_int = 6;
+        pub const F_SETLKW: ::c_int = 7;
+    } else {
+
+    }
+}
+pub const F_GETOWN: ::c_int = 23;
+pub const F_SETOWN: ::c_int = 24;
+
+pub const F_GETLK64: ::c_int = 33;
+pub const F_SETLK64: ::c_int = 34;
+pub const F_SETLKW64: ::c_int = 35;
+
+// O_CLOEXEC is defined in notbsd/mod.rs
+pub const O_CREAT: ::c_int = 0x100;
+pub const O_DIRECTORY: ::c_int = 0x10000;
+pub const O_EXCL: ::c_int = 0x400;
+pub const O_NOCTTY: ::c_int = 0x800;
+pub const O_NOFOLLOW: ::c_int = 0x20000;
+// O_TRUNC is defined in notbsd/mod.rs
+
+pub const O_APPEND: ::c_int = 0x8;
+pub const O_DSYNC: ::c_int = 0x10;
+pub const O_NONBLOCK: ::c_int = 0x80;
+pub const O_RSYNC: ::c_int = 0x4010;
+pub const O_SYNC: ::c_int = 0x4010;
+
+pub const O_ASYNC: ::c_int = 0x1000;
+pub const O_DIRECT: ::c_int = 0x8000;
+pub const O_LARGEFILE: ::c_int = 0x2000;
+pub const O_NOATIME: ::c_int = 0x40000;
+pub const O_PATH: ::c_int = 0x200000;
+pub const O_TMPFILE: ::c_int = 0x410000;
+pub const O_NDELAY: ::c_int = ::O_NONBLOCK;
+
diff --git a/src/unix/notbsd/linux/common/b32/mod.rs b/src/unix/notbsd/linux/common/b32/mod.rs
new file mode 100644
index 0000000000000..b3a364fa70e76
--- /dev/null
+++ b/src/unix/notbsd/linux/common/b32/mod.rs
@@ -0,0 +1,33 @@
+// Native C types
+pub type c_long = i32;
+pub type c_ulong = u32;
+
+/* Header <fcntl.h> */
+cfg_if! {
+    if #[cfg(any(feature = "file_offset64", target_env = "musl"))] {
+        pub const F_GETLK: ::c_int = ::F_GETLK64;
+        pub const F_SETLK: ::c_int = ::F_SETLK64;
+        pub const F_SETLKW: ::c_int = ::F_SETLKW64;
+    } else {
+
+    }
+}
+
+cfg_if! {
+    if #[cfg(target_arch = "x86")] {
+        mod x86;
+        pub use self::x86::*;
+    } else if #[cfg(target_arch = "arm")] {
+        mod arm;
+        pub use self::arm::*;
+    } else if #[cfg(target_arch = "mips")] {
+        mod mips;
+        pub use self::mips::*;
+    } else if #[cfg(target_arch = "powerpc")] {
+        mod powerpc;
+        pub use self::powerpc::*;
+    } else {
+        // Unknown target_arch
+    }
+}
+
diff --git a/src/unix/notbsd/linux/common/b32/powerpc.rs b/src/unix/notbsd/linux/common/b32/powerpc.rs
new file mode 100644
index 0000000000000..7fa4deb880636
--- /dev/null
+++ b/src/unix/notbsd/linux/common/b32/powerpc.rs
@@ -0,0 +1,60 @@
+// Native C types
+pub type c_char = u8;
+
+/* Header <fcntl.h> */
+cfg_if! {
+    if #[cfg(any(feature = "file_offset64", target_env = "musl"))] {
+        type flock = ::flock64;
+    } else {
+        s! {
+            pub struct flock {
+                pub l_type: ::c_short,
+                pub l_whence: ::c_short,
+                pub l_start: ::off_t,
+                pub l_len: ::off_t,
+                pub l_pid: ::pid_t,
+            }
+        }
+    }
+}
+
+/* Header <fcntl.h> */
+cfg_if! {
+    if #[cfg(not(any(feature = "file_offset64", target_env = "musl")))] {
+        pub const F_GETLK: ::c_int = 5;
+        pub const F_SETLK: ::c_int = 6;
+        pub const F_SETLKW: ::c_int = 7;
+    } else {
+
+    }
+}
+pub const F_GETOWN: ::c_int = 9;
+pub const F_SETOWN: ::c_int = 8;
+
+pub const F_GETLK64: ::c_int = 12;
+pub const F_SETLK64: ::c_int = 13;
+pub const F_SETLKW64: ::c_int = 14;
+
+// O_CLOEXEC is defined in notbsd/mod.rs
+pub const O_CREAT: ::c_int = 0x40;
+pub const O_DIRECTORY: ::c_int = 0x4000;
+pub const O_EXCL: ::c_int = 0x80;
+pub const O_NOCTTY: ::c_int = 0x100;
+pub const O_NOFOLLOW: ::c_int = 0x8000;
+// O_TRUNC is defined in notbsd/mod.rs
+
+pub const O_APPEND: ::c_int = 0x400;
+pub const O_DSYNC: ::c_int = 0x1000;
+pub const O_NONBLOCK: ::c_int = 0x800;
+pub const O_RSYNC: ::c_int = 0x101000;
+pub const O_SYNC: ::c_int = 0x101000;
+
+// Here start non POSIX definitions.
+pub const O_ASYNC: ::c_int = 0x2000;
+pub const O_DIRECT: ::c_int = 0x20000;
+pub const O_LARGEFILE: ::c_int = 0x10000;
+pub const O_NOATIME: ::c_int = 0x40000;
+pub const O_PATH: ::c_int = 0x200000;
+pub const O_TMPFILE: ::c_int = 0x404000;
+pub const O_NDELAY: ::c_int = ::O_NONBLOCK;
+
diff --git a/src/unix/notbsd/linux/common/b32/x86.rs b/src/unix/notbsd/linux/common/b32/x86.rs
new file mode 100644
index 0000000000000..b68175634f50d
--- /dev/null
+++ b/src/unix/notbsd/linux/common/b32/x86.rs
@@ -0,0 +1,60 @@
+// Native C types
+pub type c_char = i8;
+
+/* Header <fcntl.h> */
+cfg_if! {
+    if #[cfg(any(feature = "file_offset64", target_env = "musl"))] {
+        type flock = ::flock64;
+    } else {
+        s! {
+            pub struct flock {
+                pub l_type: ::c_short,
+                pub l_whence: ::c_short,
+                pub l_start: ::off_t,
+                pub l_len: ::off_t,
+                pub l_pid: ::pid_t,
+            }
+        }
+    }
+}
+
+/* Header <fcntl.h> */
+cfg_if! {
+    if #[cfg(not(any(feature = "file_offset64", target_env = "musl")))] {
+        pub const F_GETLK: ::c_int = 5;
+        pub const F_SETLK: ::c_int = 6;
+        pub const F_SETLKW: ::c_int = 7;
+    } else {
+
+    }
+}
+pub const F_GETOWN: ::c_int = 9;
+pub const F_SETOWN: ::c_int = 8;
+
+pub const F_GETLK64: ::c_int = 12;
+pub const F_SETLK64: ::c_int = 13;
+pub const F_SETLKW64: ::c_int = 14;
+
+// O_CLOEXEC is defined in notbsd/mod.rs
+pub const O_CREAT: ::c_int = 0x40;
+pub const O_DIRECTORY: ::c_int = 0x10000;
+pub const O_EXCL: ::c_int = 0x80;
+pub const O_NOCTTY: ::c_int = 0x100;
+pub const O_NOFOLLOW: ::c_int = 0x20000;
+// O_TRUNC is defined in notbsd/mod.rs
+
+pub const O_APPEND: ::c_int = 0x400;
+pub const O_DSYNC: ::c_int = 0x1000;
+pub const O_NONBLOCK: ::c_int = 0x800;
+pub const O_RSYNC: ::c_int = 0x101000;
+pub const O_SYNC: ::c_int = 0x101000;
+
+// Here start non POSIX definitions.
+pub const O_ASYNC: ::c_int = 0x2000;
+pub const O_DIRECT: ::c_int = 0x4000;
+pub const O_LARGEFILE: ::c_int = 0x8000;
+pub const O_NOATIME: ::c_int = 0x40000;
+pub const O_PATH: ::c_int = 0x200000;
+pub const O_TMPFILE: ::c_int = 0x410000;
+pub const O_NDELAY: ::c_int = ::O_NONBLOCK;
+
diff --git a/src/unix/notbsd/linux/common/b64/aarch64.rs b/src/unix/notbsd/linux/common/b64/aarch64.rs
new file mode 100644
index 0000000000000..200283b7b5f80
--- /dev/null
+++ b/src/unix/notbsd/linux/common/b64/aarch64.rs
@@ -0,0 +1,33 @@
+// Native C types
+pub type c_char = u8;
+
+/* Header <fcntl.h> */
+pub const F_GETLK: ::c_int = 5;
+pub const F_SETLK: ::c_int = 6;
+pub const F_SETLKW: ::c_int = 7;
+pub const F_GETOWN: ::c_int = 9;
+pub const F_SETOWN: ::c_int = 8;
+
+// O_CLOEXEC is defined in notbsd/mod.rs
+pub const O_CREAT: ::c_int = 0x40;
+pub const O_DIRECTORY: ::c_int = 0x4000;
+pub const O_EXCL: ::c_int = 0x80;
+pub const O_NOCTTY: ::c_int = 0x100;
+pub const O_NOFOLLOW: ::c_int = 0x8000;
+// O_TRUNC is defined in notbsd/mod.rs
+
+pub const O_APPEND: ::c_int = 0x400;
+pub const O_DSYNC: ::c_int = 0x1000;
+pub const O_NONBLOCK: ::c_int = 0x800;
+pub const O_RSYNC: ::c_int = 0x101000;
+pub const O_SYNC: ::c_int = 0x101000;
+
+// Here start non POSIX definitions.
+pub const O_ASYNC: ::c_int = 0x2000;
+pub const O_DIRECT: ::c_int = 0x10000;
+pub const O_LARGEFILE: ::c_int = 0;
+pub const O_NOATIME: ::c_int = 0x40000;
+pub const O_PATH: ::c_int = 0x200000;
+pub const O_TMPFILE: ::c_int = 0x404000;
+pub const O_NDELAY: ::c_int = ::O_NONBLOCK;
+
diff --git a/src/unix/notbsd/linux/common/b64/mips64.rs b/src/unix/notbsd/linux/common/b64/mips64.rs
new file mode 100644
index 0000000000000..daf126d2db014
--- /dev/null
+++ b/src/unix/notbsd/linux/common/b64/mips64.rs
@@ -0,0 +1,32 @@
+// Native C types
+pub type c_char = i8;
+
+/* Header <fcntl.h> */
+pub const F_GETLK: ::c_int = 14;
+pub const F_SETLK: ::c_int = 6;
+pub const F_SETLKW: ::c_int = 7;
+pub const F_GETOWN: ::c_int = 23;
+pub const F_SETOWN: ::c_int = 24;
+
+// O_CLOEXEC is defined in notbsd/mod.rs
+pub const O_CREAT: ::c_int = 0x100;
+pub const O_DIRECTORY: ::c_int = 0x10000;
+pub const O_EXCL: ::c_int = 0x400;
+pub const O_NOCTTY: ::c_int = 0x800;
+pub const O_NOFOLLOW: ::c_int = 0x20000;
+// O_TRUNC is defined in notbsd/mod.rs
+
+pub const O_APPEND: ::c_int = 0x8;
+pub const O_DSYNC: ::c_int = 0x10;
+pub const O_NONBLOCK: ::c_int = 0x80;
+pub const O_RSYNC: ::c_int = 0x4010;
+pub const O_SYNC: ::c_int = 0x4010;
+
+pub const O_ASYNC: ::c_int = 0x1000;
+pub const O_DIRECT: ::c_int = 0x8000;
+pub const O_LARGEFILE: ::c_int = 0;
+pub const O_NOATIME: ::c_int = 0x40000;
+pub const O_PATH: ::c_int = 0x200000;
+pub const O_TMPFILE: ::c_int = 0x410000;
+pub const O_NDELAY: ::c_int = ::O_NONBLOCK;
+
diff --git a/src/unix/notbsd/linux/common/b64/mod.rs b/src/unix/notbsd/linux/common/b64/mod.rs
new file mode 100644
index 0000000000000..7dd2659072c12
--- /dev/null
+++ b/src/unix/notbsd/linux/common/b64/mod.rs
@@ -0,0 +1,32 @@
+// Native C types
+pub type c_long = i64;
+pub type c_ulong = u64;
+
+/* Header <fcntl.h> */
+s! {
+    pub struct flock {
+        pub l_type: ::c_short,
+        pub l_whence: ::c_short,
+        pub l_start: ::off64_t,
+        pub l_len: ::off64_t,
+        pub l_pid: ::pid_t,
+    }
+}
+
+cfg_if! {
+    if #[cfg(target_arch = "aarch64")] {
+        mod aarch64;
+        pub use self::aarch64::*;
+    } else if #[cfg(any(target_arch = "mips64"))] {
+        mod mips64;
+        pub use self::mips64::*;
+    } else if #[cfg(any(target_arch = "powerpc64"))] {
+        mod powerpc64;
+        pub use self::powerpc64::*;
+    } else if #[cfg(any(target_arch = "x86_64"))] {
+        mod x86_64;
+        pub use self::x86_64::*;
+    } else {
+        // Unknown target_arch
+    }
+}
diff --git a/src/unix/notbsd/linux/common/b64/powerpc64.rs b/src/unix/notbsd/linux/common/b64/powerpc64.rs
new file mode 100644
index 0000000000000..f53c5378d9082
--- /dev/null
+++ b/src/unix/notbsd/linux/common/b64/powerpc64.rs
@@ -0,0 +1,33 @@
+// Native C types
+pub type c_char = u8;
+
+/* Header <fcntl.h> */
+pub const F_GETLK: ::c_int = 5;
+pub const F_SETLK: ::c_int = 6;
+pub const F_SETLKW: ::c_int = 7;
+pub const F_GETOWN: ::c_int = 9;
+pub const F_SETOWN: ::c_int = 8;
+
+// O_CLOEXEC is defined in notbsd/mod.rs
+pub const O_CREAT: ::c_int = 0x40;
+pub const O_DIRECTORY: ::c_int = 0x4000;
+pub const O_EXCL: ::c_int = 0x80;
+pub const O_NOCTTY: ::c_int = 0x100;
+pub const O_NOFOLLOW: ::c_int = 0x8000;
+// O_TRUNC is defined in notbsd/mod.rs
+
+pub const O_APPEND: ::c_int = 0x400;
+pub const O_DSYNC: ::c_int = 0x1000;
+pub const O_NONBLOCK: ::c_int = 0x800;
+pub const O_RSYNC: ::c_int = 0x101000;
+pub const O_SYNC: ::c_int = 0x101000;
+
+// Here start non POSIX definitions.
+pub const O_ASYNC: ::c_int = 0x2000;
+pub const O_DIRECT: ::c_int = 0x20000;
+pub const O_LARGEFILE: ::c_int = 0;
+pub const O_NOATIME: ::c_int = 0x40000;
+pub const O_PATH: ::c_int = 0x200000;
+pub const O_TMPFILE: ::c_int = 0x404000;
+pub const O_NDELAY: ::c_int = ::O_NONBLOCK;
+
diff --git a/src/unix/notbsd/linux/common/b64/x86_64.rs b/src/unix/notbsd/linux/common/b64/x86_64.rs
new file mode 100644
index 0000000000000..b01f5cbd401ac
--- /dev/null
+++ b/src/unix/notbsd/linux/common/b64/x86_64.rs
@@ -0,0 +1,33 @@
+// Native C types
+pub type c_char = i8;
+
+/* Header <fcntl.h> */
+pub const F_GETLK: ::c_int = 5;
+pub const F_SETLK: ::c_int = 6;
+pub const F_SETLKW: ::c_int = 7;
+pub const F_GETOWN: ::c_int = 9;
+pub const F_SETOWN: ::c_int = 8;
+
+// O_CLOEXEC is defined in notbsd/mod.rs
+pub const O_CREAT: ::c_int = 0x40;
+pub const O_DIRECTORY: ::c_int = 0x10000;
+pub const O_EXCL: ::c_int = 0x80;
+pub const O_NOCTTY: ::c_int = 0x100;
+pub const O_NOFOLLOW: ::c_int = 0x20000;
+// O_TRUNC is defined in notbsd/mod.rs
+
+pub const O_APPEND: ::c_int = 0x400;
+pub const O_DSYNC: ::c_int = 0x1000;
+pub const O_NONBLOCK: ::c_int = 0x800;
+pub const O_RSYNC: ::c_int = 0x101000;
+pub const O_SYNC: ::c_int = 0x101000;
+
+// Here start non POSIX definitions.
+pub const O_ASYNC: ::c_int = 0x2000;
+pub const O_DIRECT: ::c_int = 0x4000;
+pub const O_LARGEFILE: ::c_int = 0;
+pub const O_NOATIME: ::c_int = 0x40000;
+pub const O_PATH: ::c_int = 0x200000;
+pub const O_TMPFILE: ::c_int = 0x410000;
+pub const O_NDELAY: ::c_int = ::O_NONBLOCK;
+
diff --git a/src/unix/notbsd/linux/common/mod.rs b/src/unix/notbsd/linux/common/mod.rs
new file mode 100644
index 0000000000000..59b6b96b0e721
--- /dev/null
+++ b/src/unix/notbsd/linux/common/mod.rs
@@ -0,0 +1,82 @@
+/* Header <sys/type.h> */
+cfg_if! {
+    if #[cfg(any(feature = "file_offset64", target_env = "musl"))] {
+        pub type off_t = ::off64_t;
+    } else {
+        pub type off_t = ::c_long;
+    }
+}
+pub type off64_t = ::int64_t;
+
+s! {
+    /* Header <fcntl.h> */
+    pub struct flock64 {
+        pub l_type: ::c_short,
+        pub l_whence: ::c_short,
+        pub l_start: ::off64_t,
+        pub l_len: ::off64_t,
+        pub l_pid: ::pid_t,
+    }
+}
+
+/* Header <fcntl.h> */
+pub const F_RDLCK: ::c_short = 0;
+pub const F_WRLCK: ::c_short = 1;
+pub const F_UNLCK: ::c_short = 2;
+
+// Here start non POSIX definitions.
+pub const AT_NO_AUTOMOUNT: ::c_int = 0x800;
+pub const AT_EMPTY_PATH: ::c_int = 0x1000;
+pub const AT_EACCESS: ::c_int = 0x200;
+
+pub const FAPPEND: ::c_int = ::O_APPEND;
+// The macro O_FSYNC is NOT defined in Musl, but the macro
+// FFSYNC is defined as being equal to O_FSYNC. This is
+// a bug in Musl itself, but has to be solved here for the tests to work.
+cfg_if! {
+    if #[cfg(not(target_env = "musl"))] {
+        pub const FFSYNC: ::c_int = ::O_FSYNC;
+    } else {
+
+    }
+}
+pub const FASYNC: ::c_int = ::O_ASYNC;
+pub const FNONBLOCK: ::c_int = ::O_NONBLOCK;
+pub const FNDELAY: ::c_int = ::O_NDELAY;
+
+pub const DN_ACCESS: ::c_int = 0x00000001;
+pub const DN_MODIFY: ::c_int = 0x00000002;
+pub const DN_CREATE: ::c_int = 0x00000004;
+pub const DN_DELETE: ::c_int = 0x00000008;
+pub const DN_RENAME: ::c_int = 0x00000010;
+pub const DN_ATTRIB: ::c_int = 0x00000020;
+pub const DN_MULTISHOT: ::c_int = 0x80000000;
+
+pub const FALLOC_FL_KEEP_SIZE: ::c_int = 0x01;
+pub const FALLOC_FL_PUNCH_HOLE: ::c_int = 0x02;
+
+pub const SYNC_FILE_RANGE_WAIT_BEFORE: ::c_uint = 0x01;
+pub const SYNC_FILE_RANGE_WRITE: ::c_uint = 0x02;
+pub const SYNC_FILE_RANGE_WAIT_AFTER: ::c_uint = 0x04;
+
+pub const F_SETSIG: ::c_int = 10;
+pub const F_GETSIG: ::c_int = 11;
+
+cfg_if! {
+    if #[cfg(any(target_arch = "x86",
+                 target_arch = "arm",
+                 target_arch = "mips",
+                 target_arch = "powerpc"))] {
+        mod b32;
+        pub use self::b32::*;
+    } else if #[cfg(any(target_arch = "x86_64",
+                        target_arch = "aarch64",
+                        target_arch = "mips64",
+                        target_arch = "powerpc64"))] {
+        mod b64;
+        pub use self::b64::*;
+    } else {
+        // Unknown target_arch
+    }
+}
+
diff --git a/src/unix/notbsd/linux/mips.rs b/src/unix/notbsd/linux/mips.rs
index a2143d5e2039a..5cc76c90d8200 100644
--- a/src/unix/notbsd/linux/mips.rs
+++ b/src/unix/notbsd/linux/mips.rs
@@ -1,18 +1,14 @@
-pub type c_char = i8;
-pub type c_long = i32;
-pub type c_ulong = u32;
 pub type clock_t = i32;
 pub type time_t = i32;
 pub type suseconds_t = i32;
 pub type wchar_t = i32;
-pub type off_t = i32;
 pub type ino_t = u32;
 pub type blkcnt_t = i32;
 pub type blksize_t = i32;
 pub type nlink_t = u32;
 pub type fsblkcnt_t = ::c_ulong;
 pub type fsfilcnt_t = ::c_ulong;
-pub type rlim_t = c_ulong;
+pub type rlim_t = ::c_ulong;
 
 s! {
     pub struct stat {
@@ -163,16 +159,6 @@ s! {
         pub c_cc: [::cc_t; ::NCCS],
     }
 
-    pub struct flock {
-        pub l_type: ::c_short,
-        pub l_whence: ::c_short,
-        pub l_start: ::off_t,
-        pub l_len: ::off_t,
-        pub l_sysid: ::c_long,
-        pub l_pid: ::pid_t,
-        pad: [::c_long; 4],
-    }
-
     pub struct sysinfo {
         pub uptime: ::c_long,
         pub loads: [::c_ulong; 3],
@@ -206,10 +192,6 @@ pub const FOPEN_MAX: ::c_uint = 16;
 pub const POSIX_MADV_DONTNEED: ::c_int = 4;
 pub const _SC_2_C_VERSION: ::c_int = 96;
 pub const RUSAGE_THREAD: ::c_int = 1;
-pub const O_ACCMODE: ::c_int = 3;
-pub const O_DIRECT: ::c_int = 0x8000;
-pub const O_DIRECTORY: ::c_int = 0x10000;
-pub const O_NOFOLLOW: ::c_int = 0x20000;
 pub const RUSAGE_CHILDREN: ::c_int = -1;
 pub const ST_RELATIME: ::c_ulong = 4096;
 pub const NI_MAXHOST: ::socklen_t = 1025;
@@ -222,18 +204,6 @@ pub const RLIMIT_MEMLOCK: ::c_int = 9;
 pub const RLIMIT_NLIMITS: ::c_int = 16;
 pub const RLIM_INFINITY: ::rlim_t = 0x7fffffff;
 
-pub const O_APPEND: ::c_int = 8;
-pub const O_CREAT: ::c_int = 256;
-pub const O_EXCL: ::c_int = 1024;
-pub const O_NOCTTY: ::c_int = 2048;
-pub const O_NONBLOCK: ::c_int = 128;
-pub const O_SYNC: ::c_int = 0x4010;
-pub const O_RSYNC: ::c_int = 0x4010;
-pub const O_DSYNC: ::c_int = 0x10;
-pub const O_FSYNC: ::c_int = 0x4010;
-pub const O_ASYNC: ::c_int = 0x1000;
-pub const O_NDELAY: ::c_int = 0x80;
-
 pub const SOCK_NONBLOCK: ::c_int = 128;
 
 pub const EDEADLK: ::c_int = 45;
@@ -489,12 +459,6 @@ pub const MAP_HUGETLB: ::c_int = 0x080000;
 
 pub const EFD_NONBLOCK: ::c_int = 0x80;
 
-pub const F_GETLK: ::c_int = 14;
-pub const F_GETOWN: ::c_int = 23;
-pub const F_SETOWN: ::c_int = 24;
-pub const F_SETLK: ::c_int = 6;
-pub const F_SETLKW: ::c_int = 7;
-
 pub const SFD_NONBLOCK: ::c_int = 0x80;
 
 pub const TCGETS: ::c_ulong = 0x540d;
@@ -595,6 +559,10 @@ pub const ICANON: ::tcflag_t = 0x00000002;
 pub const PENDIN: ::tcflag_t = 0x00004000;
 pub const NOFLSH: ::tcflag_t = 0x00000080;
 
+// Dirty hack to make tests pass, but it is actually already defined
+// in the `other` module.
+pub const O_FSYNC: ::c_int = ::O_SYNC;
+
 #[link(name = "util")]
 extern {
     pub fn sysctl(name: *mut ::c_int,
diff --git a/src/unix/notbsd/linux/mips64.rs b/src/unix/notbsd/linux/mips64.rs
index 7c51dffba44ac..d89786ebd70d2 100644
--- a/src/unix/notbsd/linux/mips64.rs
+++ b/src/unix/notbsd/linux/mips64.rs
@@ -1,13 +1,9 @@
 pub type blkcnt_t = i64;
 pub type blksize_t = i64;
-pub type c_char = i8;
-pub type c_long = i64;
-pub type c_ulong = u64;
 pub type fsblkcnt_t = ::c_ulong;
 pub type fsfilcnt_t = ::c_ulong;
 pub type ino_t = u64;
 pub type nlink_t = u64;
-pub type off_t = i64;
 pub type rlim_t = ::c_ulong;
 pub type suseconds_t = i64;
 pub type time_t = i64;
@@ -191,11 +187,6 @@ pub const ETIMEDOUT: ::c_int = 145;
 pub const FIOCLEX: ::c_ulong = 0x6601;
 pub const FIONBIO: ::c_ulong = 0x667e;
 pub const MAP_ANON: ::c_int = 0x800;
-pub const O_ACCMODE: ::c_int = 3;
-pub const O_APPEND: ::c_int = 8;
-pub const O_CREAT: ::c_int = 256;
-pub const O_EXCL: ::c_int = 1024;
-pub const O_NONBLOCK: ::c_int = 128;
 pub const PTHREAD_STACK_MIN: ::size_t = 131072;
 pub const RLIM_INFINITY: ::rlim_t = 0xffffffffffffffff;
 pub const SA_ONSTACK: ::c_int = 0x08000000;
@@ -212,6 +203,10 @@ pub const SO_RCVTIMEO: ::c_int = 4102;
 pub const SO_REUSEADDR: ::c_int = 4;
 pub const SO_SNDTIMEO: ::c_int = 4101;
 
+// Dirty hack to make tests pass, but it is actually already defined
+// in the `other` module.
+pub const O_FSYNC: ::c_int = ::O_SYNC;
+
 #[link(name = "util")]
 extern {
     pub fn ioctl(fd: ::c_int, request: ::c_ulong, ...) -> ::c_int;
diff --git a/src/unix/notbsd/linux/mod.rs b/src/unix/notbsd/linux/mod.rs
index 33738f4beb073..dd9308691e5f5 100644
--- a/src/unix/notbsd/linux/mod.rs
+++ b/src/unix/notbsd/linux/mod.rs
@@ -6,9 +6,7 @@ pub type useconds_t = u32;
 pub type dev_t = u64;
 pub type socklen_t = u32;
 pub type pthread_t = c_ulong;
-pub type mode_t = u32;
 pub type ino64_t = u64;
-pub type off64_t = i64;
 pub type blkcnt64_t = i64;
 pub type rlim64_t = u64;
 pub type key_t = ::c_int;
@@ -19,6 +17,9 @@ pub type nl_item = ::c_int;
 
 pub enum fpos64_t {} // TODO: fill this out with a struct
 
+/* Header <sys/type.h> */
+pub type mode_t = ::uint32_t;
+
 s! {
     pub struct dirent {
         pub d_ino: ::ino_t,
@@ -541,12 +542,6 @@ extern {
                     offset: ::off64_t,
                     whence: ::c_int) -> ::c_int;
     pub fn ftello64(stream: *mut ::FILE) -> ::off64_t;
-    pub fn fallocate(fd: ::c_int, mode: ::c_int,
-                     offset: ::off_t, len: ::off_t) -> ::c_int;
-    pub fn posix_fallocate(fd: ::c_int, offset: ::off_t,
-                           len: ::off_t) -> ::c_int;
-    pub fn readahead(fd: ::c_int, offset: ::off64_t,
-                     count: ::size_t) -> ::ssize_t;
     pub fn getxattr(path: *const c_char, name: *const c_char,
                     value: *mut ::c_void, size: ::size_t) -> ::ssize_t;
     pub fn lgetxattr(path: *const c_char, name: *const c_char,
@@ -660,6 +655,17 @@ extern {
                     mode: ::mode_t) -> ::c_int;
     pub fn if_nameindex() -> *mut if_nameindex;
     pub fn if_freenameindex(ptr: *mut if_nameindex);
+
+    /* Header <fcntl.h> */
+    // Here start non POSIX definitions.
+    pub fn fallocate(fd: ::c_int, mode: ::c_int,
+                     offset: ::off_t, len: ::off_t) -> ::c_int;
+    pub fn fallocate64(fd: ::c_int, mode: ::c_int,
+                       offset: ::off64_t, len: ::off64_t) -> ::c_int;
+    pub fn readahead(fd: ::c_int, offset: ::off64_t,
+                     count: ::size_t) -> ::ssize_t;
+    pub fn sync_file_range(fd: ::c_int, from: ::off64_t, to: ::off64_t,
+                           flags: ::c_uint) -> ::c_int;
 }
 
 cfg_if! {
@@ -667,14 +673,22 @@ cfg_if! {
                  target_os = "emscripten"))] {
         mod musl;
         pub use self::musl::*;
+        mod common;
+        pub use self::common::*;
     } else if #[cfg(any(target_arch = "mips", target_arch = "mipsel"))] {
         mod mips;
         pub use self::mips::*;
+        mod common;
+        pub use self::common::*;
     } else if #[cfg(any(target_arch = "mips64"))] {
         mod mips64;
         pub use self::mips64::*;
+        mod common;
+        pub use self::common::*;
     } else {
         mod other;
         pub use self::other::*;
+        mod common;
+        pub use self::common::*;
     }
 }
diff --git a/src/unix/notbsd/linux/musl/b32/arm.rs b/src/unix/notbsd/linux/musl/b32/arm.rs
index 2f27e31136a8b..022f9105328f4 100644
--- a/src/unix/notbsd/linux/musl/b32/arm.rs
+++ b/src/unix/notbsd/linux/musl/b32/arm.rs
@@ -1,4 +1,3 @@
-pub type c_char = u8;
 pub type wchar_t = u32;
 
 s! {
@@ -92,11 +91,6 @@ s! {
     }
 }
 
-pub const O_DIRECT: ::c_int = 0x4000;
-pub const O_DIRECTORY: ::c_int = 0x10000;
-pub const O_NOFOLLOW: ::c_int = 0x20000;
-pub const O_ASYNC: ::c_int = 0x2000;
-
 pub const FIOCLEX: ::c_int = 0x5451;
 pub const FIONBIO: ::c_int = 0x5421;
 
@@ -106,15 +100,6 @@ pub const RLIMIT_AS: ::c_int = 9;
 pub const RLIMIT_NPROC: ::c_int = 6;
 pub const RLIMIT_MEMLOCK: ::c_int = 8;
 
-pub const O_APPEND: ::c_int = 1024;
-pub const O_CREAT: ::c_int = 64;
-pub const O_EXCL: ::c_int = 128;
-pub const O_NOCTTY: ::c_int = 256;
-pub const O_NONBLOCK: ::c_int = 2048;
-pub const O_SYNC: ::c_int = 1052672;
-pub const O_RSYNC: ::c_int = 1052672;
-pub const O_DSYNC: ::c_int = 4096;
-
 pub const SOCK_NONBLOCK: ::c_int = 2048;
 
 pub const MAP_ANON: ::c_int = 0x0020;
@@ -267,12 +252,6 @@ pub const EXTPROC: ::tcflag_t = 0x00010000;
 
 pub const MAP_HUGETLB: ::c_int = 0x040000;
 
-pub const F_GETLK: ::c_int = 12;
-pub const F_GETOWN: ::c_int = 9;
-pub const F_SETLK: ::c_int = 13;
-pub const F_SETLKW: ::c_int = 14;
-pub const F_SETOWN: ::c_int = 8;
-
 pub const VEOF: usize = 4;
 pub const VEOL: usize = 11;
 pub const VEOL2: usize = 16;
diff --git a/src/unix/notbsd/linux/musl/b32/asmjs.rs b/src/unix/notbsd/linux/musl/b32/asmjs.rs
index 991196c2a0480..6a9f1f65408a3 100644
--- a/src/unix/notbsd/linux/musl/b32/asmjs.rs
+++ b/src/unix/notbsd/linux/musl/b32/asmjs.rs
@@ -93,8 +93,6 @@ s! {
 }
 
 pub const O_DIRECT: ::c_int = 0x4000;
-pub const O_DIRECTORY: ::c_int = 0x10000;
-pub const O_NOFOLLOW: ::c_int = 0x20000;
 pub const O_ASYNC: ::c_int = 0x2000;
 
 pub const FIOCLEX: ::c_int = 0x5451;
@@ -106,15 +104,6 @@ pub const RLIMIT_AS: ::c_int = 9;
 pub const RLIMIT_NPROC: ::c_int = 6;
 pub const RLIMIT_MEMLOCK: ::c_int = 8;
 
-pub const O_APPEND: ::c_int = 1024;
-pub const O_CREAT: ::c_int = 64;
-pub const O_EXCL: ::c_int = 128;
-pub const O_NOCTTY: ::c_int = 256;
-pub const O_NONBLOCK: ::c_int = 2048;
-pub const O_SYNC: ::c_int = 1052672;
-pub const O_RSYNC: ::c_int = 1052672;
-pub const O_DSYNC: ::c_int = 4096;
-
 pub const SOCK_NONBLOCK: ::c_int = 2048;
 
 pub const MAP_ANON: ::c_int = 0x0020;
@@ -318,3 +307,20 @@ pub const POSIX_MADV_DONTNEED: ::c_int = 0;
 pub const RUSAGE_CHILDREN: ::c_int = 1;
 pub const POLLWRNORM: ::c_short = 0x100;
 pub const POLLWRBAND: ::c_short = 0x200;
+
+/* Header <fcntl.h> */
+
+// O_CLOEXEC is defined in notbsd/mod.rs
+pub const O_CREAT: ::c_int = 0x40;
+pub const O_DIRECTORY: ::c_int = 0x10000;
+pub const O_EXCL: ::c_int = 0x80;
+pub const O_NOCTTY: ::c_int = 0x100;
+pub const O_NOFOLLOW: ::c_int = 0x20000;
+// O_TRUNC is defined in notbsd/mod.rs
+
+pub const O_APPEND: ::c_int = 0x400;
+pub const O_DSYNC: ::c_int = 0x1000;
+pub const O_NONBLOCK: ::c_int = 0x800;
+pub const O_RSYNC: ::c_int = 0x101000;
+pub const O_SYNC: ::c_int = 0x101000;
+
diff --git a/src/unix/notbsd/linux/musl/b32/mips.rs b/src/unix/notbsd/linux/musl/b32/mips.rs
index 88542c45b4fde..2dc0a813d0baf 100644
--- a/src/unix/notbsd/linux/musl/b32/mips.rs
+++ b/src/unix/notbsd/linux/musl/b32/mips.rs
@@ -1,4 +1,3 @@
-pub type c_char = i8;
 pub type wchar_t = ::c_int;
 
 s! {
@@ -91,11 +90,6 @@ s! {
     }
 }
 
-pub const O_DIRECT: ::c_int = 0o100000;
-pub const O_DIRECTORY: ::c_int = 0o200000;
-pub const O_NOFOLLOW: ::c_int = 0o400000;
-pub const O_ASYNC: ::c_int = 0o10000;
-
 pub const FIOCLEX: ::c_int = 0x6601;
 pub const FIONBIO: ::c_int = 0x667E;
 
@@ -105,15 +99,6 @@ pub const RLIMIT_AS: ::c_int = 6;
 pub const RLIMIT_NPROC: ::c_int = 8;
 pub const RLIMIT_MEMLOCK: ::c_int = 9;
 
-pub const O_APPEND: ::c_int = 0o010;
-pub const O_CREAT: ::c_int = 0o400;
-pub const O_EXCL: ::c_int = 0o2000;
-pub const O_NOCTTY: ::c_int = 0o4000;
-pub const O_NONBLOCK: ::c_int = 0o200;
-pub const O_SYNC: ::c_int = 0o40020;
-pub const O_RSYNC: ::c_int = 0o40020;
-pub const O_DSYNC: ::c_int = 0o020;
-
 pub const SOCK_NONBLOCK: ::c_int = 0o200;
 
 pub const MAP_ANON: ::c_int = 0x800;
@@ -266,12 +251,6 @@ pub const EXTPROC: ::tcflag_t = 0o200000;
 
 pub const MAP_HUGETLB: ::c_int = 0x80000;
 
-pub const F_GETLK: ::c_int = 33;
-pub const F_GETOWN: ::c_int = 23;
-pub const F_SETLK: ::c_int = 34;
-pub const F_SETLKW: ::c_int = 35;
-pub const F_SETOWN: ::c_int = 24;
-
 pub const VEOF: usize = 16;
 pub const VEOL: usize = 17;
 pub const VEOL2: usize = 6;
diff --git a/src/unix/notbsd/linux/musl/b32/mod.rs b/src/unix/notbsd/linux/musl/b32/mod.rs
index 6ae90bd04eb93..cafdea0180b88 100644
--- a/src/unix/notbsd/linux/musl/b32/mod.rs
+++ b/src/unix/notbsd/linux/musl/b32/mod.rs
@@ -1,5 +1,3 @@
-pub type c_long = i32;
-pub type c_ulong = u32;
 pub type nlink_t = u32;
 
 s! {
diff --git a/src/unix/notbsd/linux/musl/b32/x86.rs b/src/unix/notbsd/linux/musl/b32/x86.rs
index 593c37a261620..8eeceadd587b2 100644
--- a/src/unix/notbsd/linux/musl/b32/x86.rs
+++ b/src/unix/notbsd/linux/musl/b32/x86.rs
@@ -1,4 +1,3 @@
-pub type c_char = i8;
 pub type wchar_t = i32;
 
 s! {
@@ -105,11 +104,6 @@ s! {
     }
 }
 
-pub const O_DIRECT: ::c_int = 0x4000;
-pub const O_DIRECTORY: ::c_int = 0x10000;
-pub const O_NOFOLLOW: ::c_int = 0x20000;
-pub const O_ASYNC: ::c_int = 0x2000;
-
 pub const FIOCLEX: ::c_int = 0x5451;
 pub const FIONBIO: ::c_int = 0x5421;
 
@@ -119,15 +113,6 @@ pub const RLIMIT_AS: ::c_int = 9;
 pub const RLIMIT_NPROC: ::c_int = 6;
 pub const RLIMIT_MEMLOCK: ::c_int = 8;
 
-pub const O_APPEND: ::c_int = 1024;
-pub const O_CREAT: ::c_int = 64;
-pub const O_EXCL: ::c_int = 128;
-pub const O_NOCTTY: ::c_int = 256;
-pub const O_NONBLOCK: ::c_int = 2048;
-pub const O_SYNC: ::c_int = 1052672;
-pub const O_RSYNC: ::c_int = 1052672;
-pub const O_DSYNC: ::c_int = 4096;
-
 pub const SOCK_NONBLOCK: ::c_int = 2048;
 
 pub const MAP_ANON: ::c_int = 0x0020;
@@ -281,12 +266,6 @@ pub const EXTPROC: ::tcflag_t = 0x00010000;
 pub const MAP_HUGETLB: ::c_int = 0x040000;
 pub const MAP_32BIT: ::c_int = 0x0040;
 
-pub const F_GETLK: ::c_int = 12;
-pub const F_GETOWN: ::c_int = 9;
-pub const F_SETLK: ::c_int = 13;
-pub const F_SETLKW: ::c_int = 14;
-pub const F_SETOWN: ::c_int = 8;
-
 pub const VEOF: usize = 4;
 pub const VEOL: usize = 11;
 pub const VEOL2: usize = 16;
diff --git a/src/unix/notbsd/linux/musl/b64/aarch64.rs b/src/unix/notbsd/linux/musl/b64/aarch64.rs
index 23f7dd35e5c98..51db30f2f1a67 100644
--- a/src/unix/notbsd/linux/musl/b64/aarch64.rs
+++ b/src/unix/notbsd/linux/musl/b64/aarch64.rs
@@ -1,3 +1 @@
-pub type c_char = u8;
-
 pub const SYS_perf_event_open: ::c_long = 241;
diff --git a/src/unix/notbsd/linux/musl/b64/mod.rs b/src/unix/notbsd/linux/musl/b64/mod.rs
index 227bffa1368cc..7f65af4a467e8 100644
--- a/src/unix/notbsd/linux/musl/b64/mod.rs
+++ b/src/unix/notbsd/linux/musl/b64/mod.rs
@@ -1,6 +1,4 @@
 pub type wchar_t = i32;
-pub type c_long = i64;
-pub type c_ulong = u64;
 pub type nlink_t = u64;
 
 s! {
@@ -116,11 +114,6 @@ s! {
 pub const __SIZEOF_PTHREAD_RWLOCK_T: usize = 56;
 pub const __SIZEOF_PTHREAD_MUTEX_T: usize = 40;
 
-pub const O_DIRECT: ::c_int = 0x4000;
-pub const O_DIRECTORY: ::c_int = 0x10000;
-pub const O_NOFOLLOW: ::c_int = 0x20000;
-pub const O_ASYNC: ::c_int = 0x2000;
-
 pub const FIOCLEX: ::c_int = 0x5451;
 pub const FIONBIO: ::c_int = 0x5421;
 
@@ -130,15 +123,6 @@ pub const RLIMIT_AS: ::c_int = 9;
 pub const RLIMIT_NPROC: ::c_int = 6;
 pub const RLIMIT_MEMLOCK: ::c_int = 8;
 
-pub const O_APPEND: ::c_int = 1024;
-pub const O_CREAT: ::c_int = 64;
-pub const O_EXCL: ::c_int = 128;
-pub const O_NOCTTY: ::c_int = 256;
-pub const O_NONBLOCK: ::c_int = 2048;
-pub const O_SYNC: ::c_int = 1052672;
-pub const O_RSYNC: ::c_int = 1052672;
-pub const O_DSYNC: ::c_int = 4096;
-
 pub const SOCK_NONBLOCK: ::c_int = 2048;
 
 pub const MAP_ANON: ::c_int = 0x0020;
@@ -292,12 +276,6 @@ pub const EXTPROC: ::tcflag_t = 0x00010000;
 
 pub const MAP_HUGETLB: ::c_int = 0x040000;
 
-pub const F_GETLK: ::c_int = 5;
-pub const F_GETOWN: ::c_int = 9;
-pub const F_SETLK: ::c_int = 6;
-pub const F_SETLKW: ::c_int = 7;
-pub const F_SETOWN: ::c_int = 8;
-
 pub const VEOF: usize = 4;
 pub const VEOL: usize = 11;
 pub const VEOL2: usize = 16;
diff --git a/src/unix/notbsd/linux/musl/b64/powerpc64.rs b/src/unix/notbsd/linux/musl/b64/powerpc64.rs
index 4b8ca10aab57b..bb81863654136 100644
--- a/src/unix/notbsd/linux/musl/b64/powerpc64.rs
+++ b/src/unix/notbsd/linux/musl/b64/powerpc64.rs
@@ -1,3 +1 @@
-pub type c_char = u8;
-
 pub const SYS_perf_event_open: ::c_long = 319;
diff --git a/src/unix/notbsd/linux/musl/b64/x86_64.rs b/src/unix/notbsd/linux/musl/b64/x86_64.rs
index 2cfd903ca84fb..02324dae3029f 100644
--- a/src/unix/notbsd/linux/musl/b64/x86_64.rs
+++ b/src/unix/notbsd/linux/musl/b64/x86_64.rs
@@ -1,5 +1,3 @@
-pub type c_char = i8;
-
 s! {
     pub struct mcontext_t {
         __private: [u64; 32],
diff --git a/src/unix/notbsd/linux/musl/mod.rs b/src/unix/notbsd/linux/musl/mod.rs
index b9fb3d42f3ac3..5d3d92438f75f 100644
--- a/src/unix/notbsd/linux/musl/mod.rs
+++ b/src/unix/notbsd/linux/musl/mod.rs
@@ -1,11 +1,10 @@
-pub type clock_t = c_long;
-pub type time_t = c_long;
-pub type suseconds_t = c_long;
+pub type clock_t = ::c_long;
+pub type time_t = ::c_long;
+pub type suseconds_t = ::c_long;
 pub type ino_t = u64;
-pub type off_t = i64;
 pub type blkcnt_t = i64;
 
-pub type blksize_t = c_long;
+pub type blksize_t = ::c_long;
 pub type fsblkcnt_t = ::c_ulonglong;
 pub type fsfilcnt_t = ::c_ulonglong;
 pub type rlim_t = ::c_ulonglong;
@@ -41,14 +40,6 @@ s! {
         pub __c_ospeed: ::speed_t,
     }
 
-    pub struct flock {
-        pub l_type: ::c_short,
-        pub l_whence: ::c_short,
-        pub l_start: ::off_t,
-        pub l_len: ::off_t,
-        pub l_pid: ::pid_t,
-    }
-
     pub struct sysinfo {
         pub uptime: ::c_ulong,
         pub loads: [::c_ulong; 3],
@@ -70,8 +61,6 @@ s! {
 pub const BUFSIZ: ::c_uint = 1024;
 pub const TMP_MAX: ::c_uint = 10000;
 pub const FOPEN_MAX: ::c_uint = 1000;
-pub const O_ACCMODE: ::c_int = 0o10000003;
-pub const O_NDELAY: ::c_int = O_NONBLOCK;
 pub const NI_MAXHOST: ::socklen_t = 255;
 pub const PTHREAD_STACK_MIN: ::size_t = 2048;
 
@@ -94,9 +83,6 @@ pub const TCP_TIMESTAMP: ::c_int = 24;
 
 pub const SIGUNUSED: ::c_int = ::SIGSYS;
 
-pub const FALLOC_FL_KEEP_SIZE: ::c_int = 0x01;
-pub const FALLOC_FL_PUNCH_HOLE: ::c_int = 0x02;
-
 pub const __SIZEOF_PTHREAD_CONDATTR_T: usize = 4;
 pub const __SIZEOF_PTHREAD_MUTEXATTR_T: usize = 4;
 
@@ -219,6 +205,36 @@ pub const ICANON: ::tcflag_t = 0x00000002;
 pub const PENDIN: ::tcflag_t = 0x00004000;
 pub const NOFLSH: ::tcflag_t = 0x00000080;
 
+/* Header <fcntl.h> */
+pub const O_ACCMODE: ::c_int = 0x3 | ::O_SEARCH;
+
+// Both are defined in POSIX standard, but absent from other libc.
+pub const O_SEARCH: ::c_int = ::O_PATH;
+pub const O_EXEC: ::c_int = ::O_PATH;
+
+// Here start non POSIX definitions.
+pub const F_OFD_GETLK: ::c_int = 36;
+pub const F_OFD_SETLK: ::c_int = 37;
+pub const F_OFD_SETLKW: ::c_int = 38;
+
+pub const F_CANCELLK: ::c_int = 1029;
+pub const F_ADD_SEALS: ::c_int = 1033;
+pub const F_GET_SEALS: ::c_int = 1034;
+
+pub const F_SEAL_SEAL: ::c_int = 0x0001;
+pub const F_SEAL_SHRINK: ::c_int = 0x0002;
+pub const F_SEAL_GROW: ::c_int = 0x0004;
+pub const F_SEAL_WRITE: ::c_int = 0x0008;
+
+pub const F_OWNER_TID: ::c_int = 0;
+pub const F_OWNER_PID: ::c_int = 1;
+pub const F_OWNER_PGRP: ::c_int = 2;
+pub const F_OWNER_GID: ::c_int = ::F_OWNER_PGRP;
+
+pub const F_SETOWN_EX: ::c_int = 15;
+pub const F_GETOWN_EX: ::c_int = 16;
+pub const F_GETOWNER_UIDS: ::c_int = 17;
+
 extern {
     pub fn ioctl(fd: ::c_int, request: ::c_int, ...) -> ::c_int;
     pub fn ptrace(request: ::c_int, ...) -> ::c_long;
diff --git a/src/unix/notbsd/linux/other/b32/arm.rs b/src/unix/notbsd/linux/other/b32/arm.rs
index f3871f3c2ffba..dfd95c711fa8f 100644
--- a/src/unix/notbsd/linux/other/b32/arm.rs
+++ b/src/unix/notbsd/linux/other/b32/arm.rs
@@ -1,4 +1,3 @@
-pub type c_char = u8;
 pub type wchar_t = u32;
 
 s! {
@@ -55,10 +54,6 @@ s! {
     }
 }
 
-pub const O_DIRECT: ::c_int = 0x10000;
-pub const O_DIRECTORY: ::c_int = 0x4000;
-pub const O_NOFOLLOW: ::c_int = 0x8000;
-
 pub const MAP_LOCKED: ::c_int = 0x02000;
 pub const MAP_NORESERVE: ::c_int = 0x04000;
 
diff --git a/src/unix/notbsd/linux/other/b32/mod.rs b/src/unix/notbsd/linux/other/b32/mod.rs
index 48c3502ada1b6..4a936070f3406 100644
--- a/src/unix/notbsd/linux/other/b32/mod.rs
+++ b/src/unix/notbsd/linux/other/b32/mod.rs
@@ -1,12 +1,9 @@
 //! 32-bit specific definitions for linux-like values
 
-pub type c_long = i32;
-pub type c_ulong = u32;
 pub type clock_t = i32;
 pub type time_t = i32;
 pub type suseconds_t = i32;
 pub type ino_t = u32;
-pub type off_t = i32;
 pub type blkcnt_t = i32;
 pub type __fsword_t = i32;
 
diff --git a/src/unix/notbsd/linux/other/b32/powerpc.rs b/src/unix/notbsd/linux/other/b32/powerpc.rs
index ef21eda0ce5cc..6c010ffbe96fe 100644
--- a/src/unix/notbsd/linux/other/b32/powerpc.rs
+++ b/src/unix/notbsd/linux/other/b32/powerpc.rs
@@ -1,4 +1,3 @@
-pub type c_char = u8;
 pub type wchar_t = i32;
 
 s! {
@@ -55,10 +54,6 @@ s! {
     }
 }
 
-pub const O_DIRECT: ::c_int = 0x20000;
-pub const O_DIRECTORY: ::c_int = 0x4000;
-pub const O_NOFOLLOW: ::c_int = 0x8000;
-
 pub const MAP_LOCKED: ::c_int = 0x00080;
 pub const MAP_NORESERVE: ::c_int = 0x00040;
 
diff --git a/src/unix/notbsd/linux/other/b32/x86.rs b/src/unix/notbsd/linux/other/b32/x86.rs
index 6f8587a89363b..9a605798fcac0 100644
--- a/src/unix/notbsd/linux/other/b32/x86.rs
+++ b/src/unix/notbsd/linux/other/b32/x86.rs
@@ -1,4 +1,3 @@
-pub type c_char = i8;
 pub type wchar_t = i32;
 pub type greg_t = i32;
 
@@ -89,10 +88,6 @@ s! {
     }
 }
 
-pub const O_DIRECT: ::c_int = 0x4000;
-pub const O_DIRECTORY: ::c_int = 0x10000;
-pub const O_NOFOLLOW: ::c_int = 0x20000;
-
 pub const MAP_LOCKED: ::c_int = 0x02000;
 pub const MAP_NORESERVE: ::c_int = 0x04000;
 pub const MAP_32BIT: ::c_int = 0x0040;
diff --git a/src/unix/notbsd/linux/other/b64/aarch64.rs b/src/unix/notbsd/linux/other/b64/aarch64.rs
index d9f940bc399af..89e9e5cd9cfca 100644
--- a/src/unix/notbsd/linux/other/b64/aarch64.rs
+++ b/src/unix/notbsd/linux/other/b64/aarch64.rs
@@ -1,6 +1,5 @@
 //! AArch64-specific definitions for 64-bit linux-like values
 
-pub type c_char = u8;
 pub type wchar_t = u32;
 pub type nlink_t = u32;
 pub type blksize_t = i32;
@@ -86,10 +85,6 @@ pub const __SIZEOF_PTHREAD_CONDATTR_T: usize = 8;
 pub const __SIZEOF_PTHREAD_MUTEX_T: usize = 48;
 pub const __SIZEOF_PTHREAD_MUTEXATTR_T: usize = 8;
 
-pub const O_DIRECT: ::c_int = 0x10000;
-pub const O_DIRECTORY: ::c_int = 0x4000;
-pub const O_NOFOLLOW: ::c_int = 0x8000;
-
 pub const MAP_LOCKED: ::c_int = 0x02000;
 pub const MAP_NORESERVE: ::c_int = 0x04000;
 
diff --git a/src/unix/notbsd/linux/other/b64/mod.rs b/src/unix/notbsd/linux/other/b64/mod.rs
index ccf99881f76cc..3fc3fc2283087 100644
--- a/src/unix/notbsd/linux/other/b64/mod.rs
+++ b/src/unix/notbsd/linux/other/b64/mod.rs
@@ -1,12 +1,9 @@
 //! 64-bit specific definitions for linux-like values
 
-pub type c_long = i64;
-pub type c_ulong = u64;
 pub type clock_t = i64;
 pub type time_t = i64;
 pub type suseconds_t = i64;
 pub type ino_t = u64;
-pub type off_t = i64;
 pub type blkcnt_t = i64;
 pub type __fsword_t = ::c_long;
 
diff --git a/src/unix/notbsd/linux/other/b64/powerpc64.rs b/src/unix/notbsd/linux/other/b64/powerpc64.rs
index c5ce962e39aa1..46f5c3423d778 100644
--- a/src/unix/notbsd/linux/other/b64/powerpc64.rs
+++ b/src/unix/notbsd/linux/other/b64/powerpc64.rs
@@ -1,6 +1,5 @@
 //! PowerPC64-specific definitions for 64-bit linux-like values
 
-pub type c_char = u8;
 pub type wchar_t = i32;
 pub type nlink_t = u64;
 pub type blksize_t = i64;
@@ -83,10 +82,6 @@ pub const __SIZEOF_PTHREAD_CONDATTR_T: usize = 4;
 pub const __SIZEOF_PTHREAD_MUTEX_T: usize = 40;
 pub const __SIZEOF_PTHREAD_MUTEXATTR_T: usize = 4;
 
-pub const O_DIRECTORY: ::c_int = 0x4000;
-pub const O_NOFOLLOW: ::c_int = 0x8000;
-pub const O_DIRECT: ::c_int = 0x20000;
-
 pub const MAP_LOCKED: ::c_int = 0x00080;
 pub const MAP_NORESERVE: ::c_int = 0x00040;
 
diff --git a/src/unix/notbsd/linux/other/b64/x86_64.rs b/src/unix/notbsd/linux/other/b64/x86_64.rs
index f19a9ffe4adcd..3942b83de4010 100644
--- a/src/unix/notbsd/linux/other/b64/x86_64.rs
+++ b/src/unix/notbsd/linux/other/b64/x86_64.rs
@@ -1,6 +1,5 @@
 //! x86_64-specific definitions for 64-bit linux-like values
 
-pub type c_char = i8;
 pub type wchar_t = i32;
 pub type nlink_t = u64;
 pub type blksize_t = i64;
@@ -124,10 +123,6 @@ pub const __SIZEOF_PTHREAD_CONDATTR_T: usize = 4;
 pub const __SIZEOF_PTHREAD_MUTEX_T: usize = 40;
 pub const __SIZEOF_PTHREAD_MUTEXATTR_T: usize = 4;
 
-pub const O_DIRECT: ::c_int = 0x4000;
-pub const O_DIRECTORY: ::c_int = 0x10000;
-pub const O_NOFOLLOW: ::c_int = 0x20000;
-
 pub const MAP_LOCKED: ::c_int = 0x02000;
 pub const MAP_NORESERVE: ::c_int = 0x04000;
 pub const MAP_32BIT: ::c_int = 0x0040;
diff --git a/src/unix/notbsd/linux/other/gnu.rs b/src/unix/notbsd/linux/other/gnu.rs
new file mode 100644
index 0000000000000..2a88f91d1f236
--- /dev/null
+++ b/src/unix/notbsd/linux/other/gnu.rs
@@ -0,0 +1,51 @@
+s! {
+    /* Header <fcntl.h> */
+    pub struct file_handle {
+        pub handle_bytes: ::c_uint,
+        pub handle_type: ::c_int,
+//        pub f_handle: [::c_uchar],
+    }
+}
+
+/* Header <fcntl.h> */
+pub const F_OFD_GETLK: ::c_int = 36;
+pub const F_OFD_SETLK: ::c_int = 37;
+pub const F_OFD_SETLKW: ::c_int = 38;
+
+// Here start non POSIX definitions.
+/* Defined in glibc but doesn’t seem to exist for Linux.
+pub const FSYNC: ::c_int = ::O_SYNC;)
+*/
+
+pub const F_OWNER_TID: ::c_int = 0;
+pub const F_OWNER_PID: ::c_int = 1;
+pub const F_OWNER_PGRP: ::c_int = 2;
+pub const F_OWNER_GID: ::c_int = ::F_OWNER_PGRP;
+
+pub const FALLOC_FL_COLLAPSE_RANGE: ::c_int = 0x08;
+pub const FALLOC_FL_ZERO_RANGE: ::c_int = 0x10;
+
+pub const MAX_HANDLE_SZ: ::size_t = 128;
+
+/* Defined in glibc but don’t seem to exist for Linux.
+pub const O_SHLOCK: ::c_int = 0x0010;
+pub const O_EXLOCK: ::c_int = 0x0020;
+
+pub const FREAD: ::c_int = 1;
+pub const FWRITE: ::c_int = 2;
+*/
+
+pub const F_SETOWN_EX: ::c_int = 15;
+pub const F_GETOWN_EX: ::c_int = 16;
+
+extern {
+    /* Header <fcntl.h> */
+    pub fn name_to_handle_at(dfd: ::c_int,
+                             name: *const ::c_char,
+                             handle: *mut ::file_handle,
+                             mnt_id: *mut ::c_int,
+                             flags: ::c_int) -> ::c_int;
+    pub fn open_by_handle_at(mountdirfd: ::c_int,
+                             handle: *mut ::file_handle,
+                             flags: ::c_int) -> ::c_int;
+}
diff --git a/src/unix/notbsd/linux/other/mod.rs b/src/unix/notbsd/linux/other/mod.rs
index ac3e0c39797a4..515b4878d716e 100644
--- a/src/unix/notbsd/linux/other/mod.rs
+++ b/src/unix/notbsd/linux/other/mod.rs
@@ -1,6 +1,6 @@
 pub type fsblkcnt_t = ::c_ulong;
 pub type fsfilcnt_t = ::c_ulong;
-pub type rlim_t = c_ulong;
+pub type rlim_t = ::c_ulong;
 pub type __priority_which_t = ::c_uint;
 
 s! {
@@ -115,14 +115,6 @@ s! {
         pub c_ospeed: ::speed_t,
     }
 
-    pub struct flock {
-        pub l_type: ::c_short,
-        pub l_whence: ::c_short,
-        pub l_start: ::off_t,
-        pub l_len: ::off_t,
-        pub l_pid: ::pid_t,
-    }
-
     // FIXME this is actually a union
     pub struct sem_t {
         #[cfg(target_pointer_width = "32")]
@@ -156,17 +148,7 @@ pub const RLIM_INFINITY: ::rlim_t = !0;
 pub const RLIMIT_RTTIME: ::c_int = 15;
 pub const RLIMIT_NLIMITS: ::c_int = 16;
 
-pub const O_APPEND: ::c_int = 1024;
-pub const O_CREAT: ::c_int = 64;
-pub const O_EXCL: ::c_int = 128;
-pub const O_NOCTTY: ::c_int = 256;
-pub const O_NONBLOCK: ::c_int = 2048;
-pub const O_SYNC: ::c_int = 1052672;
-pub const O_RSYNC: ::c_int = 1052672;
-pub const O_DSYNC: ::c_int = 4096;
-pub const O_FSYNC: ::c_int = 0x101000;
-
-pub const SOCK_NONBLOCK: ::c_int = O_NONBLOCK;
+pub const SOCK_NONBLOCK: ::c_int = ::O_NONBLOCK;
 
 pub const LC_PAPER: ::c_int = 7;
 pub const LC_NAME: ::c_int = 8;
@@ -350,18 +332,12 @@ pub const POLLWRNORM: ::c_short = 0x100;
 pub const POLLRDBAND: ::c_short = 0x080;
 pub const POLLWRBAND: ::c_short = 0x200;
 
-pub const FALLOC_FL_KEEP_SIZE: ::c_int = 0x01;
-pub const FALLOC_FL_PUNCH_HOLE: ::c_int = 0x02;
-
 pub const BUFSIZ: ::c_uint = 8192;
 pub const TMP_MAX: ::c_uint = 238328;
 pub const FOPEN_MAX: ::c_uint = 16;
 pub const POSIX_MADV_DONTNEED: ::c_int = 4;
 pub const _SC_2_C_VERSION: ::c_int = 96;
 pub const RUSAGE_THREAD: ::c_int = 1;
-pub const O_ACCMODE: ::c_int = 3;
-pub const O_ASYNC: ::c_int = 0x2000;
-pub const O_NDELAY: ::c_int = 0x800;
 pub const RUSAGE_CHILDREN: ::c_int = -1;
 pub const ST_RELATIME: ::c_ulong = 4096;
 pub const NI_MAXHOST: ::socklen_t = 1025;
@@ -435,12 +411,6 @@ pub const MAP_HUGETLB: ::c_int = 0x040000;
 
 pub const EFD_NONBLOCK: ::c_int = 0x800;
 
-pub const F_GETLK: ::c_int = 5;
-pub const F_GETOWN: ::c_int = 9;
-pub const F_SETOWN: ::c_int = 8;
-pub const F_SETLK: ::c_int = 6;
-pub const F_SETLKW: ::c_int = 7;
-
 pub const SEEK_DATA: ::c_int = 3;
 pub const SEEK_HOLE: ::c_int = 4;
 
@@ -492,6 +462,25 @@ cfg_if! {
     }
 }
 
+pub const LOCK_SH: ::c_int = 0x1;
+pub const LOCK_EX: ::c_int = 0x2;
+pub const LOCK_NB: ::c_int = 0x4;
+pub const LOCK_UN: ::c_int = 0x8;
+
+/* Header <fcntl.h> */
+pub const O_ACCMODE: ::c_int = 3;
+
+// Here start non POSIX definitions.
+pub const F_EXLCK: ::c_short = 0x4;
+pub const F_SHLCK: ::c_short = 0x8;
+
+pub const LOCK_MAND: ::c_int = 0x20;
+pub const LOCK_READ: ::c_int = 0x40;
+pub const LOCK_WRITE: ::c_int = 0x80;
+pub const LOCK_RW: ::c_int = 0xc0;
+
+pub const O_FSYNC: ::c_int = ::O_SYNC;
+
 extern {
     pub fn utmpxname(file: *const ::c_char) -> ::c_int;
     pub fn getutxent() -> *mut utmpx;
@@ -555,3 +544,16 @@ cfg_if! {
         // Unknown target_arch
     }
 }
+
+cfg_if! {
+    if #[cfg(target_env = "gnu")] {
+        mod gnu;
+        pub use self::gnu::*;
+    } else if #[cfg(target_env = "uclibc")] {
+        mod uclibc;
+        pub use self::uclibc::*;
+    } else {
+        // Unknown target_env
+    }
+}
+
diff --git a/src/unix/notbsd/linux/other/uclibc.rs b/src/unix/notbsd/linux/other/uclibc.rs
new file mode 100644
index 0000000000000..e69de29bb2d1d
diff --git a/src/unix/notbsd/mod.rs b/src/unix/notbsd/mod.rs
index a3d60ca6cc237..10244cec88bed 100644
--- a/src/unix/notbsd/mod.rs
+++ b/src/unix/notbsd/mod.rs
@@ -184,20 +184,6 @@ pub const _IOFBF: ::c_int = 0;
 pub const _IONBF: ::c_int = 2;
 pub const _IOLBF: ::c_int = 1;
 
-pub const F_DUPFD: ::c_int = 0;
-pub const F_GETFD: ::c_int = 1;
-pub const F_SETFD: ::c_int = 2;
-pub const F_GETFL: ::c_int = 3;
-pub const F_SETFL: ::c_int = 4;
-
-// Linux-specific fcntls
-pub const F_SETLEASE: ::c_int = 1024;
-pub const F_GETLEASE: ::c_int = 1025;
-pub const F_NOTIFY: ::c_int = 1026;
-pub const F_DUPFD_CLOEXEC: ::c_int = 1030;
-pub const F_SETPIPE_SZ: ::c_int = 1031;
-pub const F_GETPIPE_SZ: ::c_int = 1032;
-
 // TODO(#235): Include file sealing fcntls once we have a way to verify them.
 
 pub const SIGTRAP: ::c_int = 5;
@@ -234,12 +220,6 @@ pub const RLIMIT_RTPRIO: ::c_int = 14;
 
 pub const RUSAGE_SELF: ::c_int = 0;
 
-pub const O_RDONLY: ::c_int = 0;
-pub const O_WRONLY: ::c_int = 1;
-pub const O_RDWR: ::c_int = 2;
-pub const O_TRUNC: ::c_int = 512;
-pub const O_CLOEXEC: ::c_int = 0x80000;
-
 pub const SOCK_CLOEXEC: ::c_int = O_CLOEXEC;
 
 pub const S_IFIFO: ::mode_t = 4096;
@@ -471,11 +451,6 @@ pub const SHUT_RD: ::c_int = 0;
 pub const SHUT_WR: ::c_int = 1;
 pub const SHUT_RDWR: ::c_int = 2;
 
-pub const LOCK_SH: ::c_int = 1;
-pub const LOCK_EX: ::c_int = 2;
-pub const LOCK_NB: ::c_int = 4;
-pub const LOCK_UN: ::c_int = 8;
-
 pub const SA_NODEFER: ::c_int = 0x40000000;
 pub const SA_RESETHAND: ::c_int = 0x80000000;
 pub const SA_RESTART: ::c_int = 0x10000000;
@@ -602,23 +577,8 @@ pub const __WNOTHREAD: ::c_int = 0x20000000;
 pub const __WALL: ::c_int = 0x40000000;
 pub const __WCLONE: ::c_int = 0x80000000;
 
-pub const SPLICE_F_MOVE: ::c_uint = 0x01;
-pub const SPLICE_F_NONBLOCK: ::c_uint = 0x02;
-pub const SPLICE_F_MORE: ::c_uint = 0x04;
-pub const SPLICE_F_GIFT: ::c_uint = 0x08;
-
 pub const RTLD_LOCAL: ::c_int = 0;
 
-pub const POSIX_FADV_NORMAL: ::c_int = 0;
-pub const POSIX_FADV_RANDOM: ::c_int = 1;
-pub const POSIX_FADV_SEQUENTIAL: ::c_int = 2;
-pub const POSIX_FADV_WILLNEED: ::c_int = 3;
-pub const POSIX_FADV_DONTNEED: ::c_int = 4;
-pub const POSIX_FADV_NOREUSE: ::c_int = 5;
-
-pub const AT_FDCWD: ::c_int = -100;
-pub const AT_SYMLINK_NOFOLLOW: ::c_int = 0x100;
-
 pub const LOG_CRON: ::c_int = 9 << 3;
 pub const LOG_AUTHPRIV: ::c_int = 10 << 3;
 pub const LOG_FTP: ::c_int = 11 << 3;
@@ -628,6 +588,46 @@ pub const PIPE_BUF: usize = 4096;
 
 pub const SI_LOAD_SHIFT: ::c_uint = 16;
 
+/* Header <fcntl.h> */
+pub const F_DUPFD: ::c_int = 0;
+pub const F_DUPFD_CLOEXEC: ::c_int = 1030;
+pub const F_GETFD: ::c_int = 1;
+pub const F_SETFD: ::c_int = 2;
+pub const F_GETFL: ::c_int = 3;
+pub const F_SETFL: ::c_int = 4;
+
+pub const O_CLOEXEC: ::c_int = 0x80000;
+pub const O_TRUNC: ::c_int = 0x200;
+
+pub const O_RDONLY: ::c_int = 0;
+pub const O_WRONLY: ::c_int = 1;
+pub const O_RDWR: ::c_int = 2;
+
+pub const AT_FDCWD: ::c_int = -100;
+// AT_EACCESS doesn’t exist in Bionic (for Android).
+pub const AT_SYMLINK_NOFOLLOW: ::c_int = 0x100;
+pub const AT_SYMLINK_FOLLOW: ::c_int = 0x400;
+pub const AT_REMOVEDIR: ::c_int = 0x200;
+
+pub const POSIX_FADV_NORMAL: ::c_int = 0;
+pub const POSIX_FADV_RANDOM: ::c_int = 1;
+pub const POSIX_FADV_SEQUENTIAL: ::c_int = 2;
+pub const POSIX_FADV_WILLNEED: ::c_int = 3;
+pub const POSIX_FADV_DONTNEED: ::c_int = 4;
+pub const POSIX_FADV_NOREUSE: ::c_int = 5;
+
+// Here start non POSIX definitions.
+pub const F_SETLEASE: ::c_int = 1024;
+pub const F_GETLEASE: ::c_int = 1025;
+pub const F_NOTIFY: ::c_int = 1026;
+pub const F_SETPIPE_SZ: ::c_int = 1031;
+pub const F_GETPIPE_SZ: ::c_int = 1032;
+
+pub const SPLICE_F_MOVE: ::c_uint = 0x01;
+pub const SPLICE_F_NONBLOCK: ::c_uint = 0x02;
+pub const SPLICE_F_MORE: ::c_uint = 0x04;
+pub const SPLICE_F_GIFT: ::c_uint = 0x08;
+
 f! {
     pub fn FD_CLR(fd: ::c_int, set: *mut fd_set) -> () {
         let fd = fd as usize;
@@ -753,23 +753,6 @@ extern {
                     in_fd: ::c_int,
                     offset: *mut off_t,
                     count: ::size_t) -> ::ssize_t;
-    pub fn splice(fd_in: ::c_int,
-                  off_in: *mut ::loff_t,
-                  fd_out: ::c_int,
-                  off_out: *mut ::loff_t,
-                  len: ::size_t,
-                  flags: ::c_uint) -> ::ssize_t;
-    pub fn tee(fd_in: ::c_int,
-               fd_out: ::c_int,
-               len: ::size_t,
-               flags: ::c_uint) -> ::ssize_t;
-    pub fn vmsplice(fd: ::c_int,
-                    iov: *const ::iovec,
-                    nr_segs: ::size_t,
-                    flags: ::c_uint) -> ::ssize_t;
-
-    pub fn posix_fadvise(fd: ::c_int, offset: ::off_t, len: ::off_t,
-                         advise: ::c_int) -> ::c_int;
     pub fn futimens(fd: ::c_int, times: *const ::timespec) -> ::c_int;
     pub fn utimensat(dirfd: ::c_int, path: *const ::c_char,
                      times: *const ::timespec, flag: ::c_int) -> ::c_int;
@@ -779,7 +762,6 @@ extern {
                      locale: *const ::c_char,
                      base: ::locale_t) -> ::locale_t;
     pub fn uselocale(loc: ::locale_t) -> ::locale_t;
-    pub fn creat64(path: *const c_char, mode: mode_t) -> ::c_int;
     pub fn fstat64(fildes: ::c_int, buf: *mut stat64) -> ::c_int;
     pub fn ftruncate64(fd: ::c_int, length: off64_t) -> ::c_int;
     pub fn getrlimit64(resource: ::c_int, rlim: *mut rlimit64) -> ::c_int;
@@ -792,7 +774,6 @@ extern {
                   fd: ::c_int,
                   offset: off64_t)
                   -> *mut ::c_void;
-    pub fn open64(path: *const c_char, oflag: ::c_int, ...) -> ::c_int;
     pub fn pread64(fd: ::c_int, buf: *mut ::c_void, count: ::size_t,
                    offset: off64_t) -> ::ssize_t;
     pub fn pwrite64(fd: ::c_int, buf: *const ::c_void, count: ::size_t,
@@ -804,8 +785,6 @@ extern {
     pub fn eventfd(init: ::c_uint, flags: ::c_int) -> ::c_int;
     pub fn sysinfo (info: *mut ::sysinfo) -> ::c_int;
 
-    pub fn openat(dirfd: ::c_int, pathname: *const ::c_char,
-                  flags: ::c_int, ...) -> ::c_int;
     pub fn faccessat(dirfd: ::c_int, pathname: *const ::c_char,
                      mode: ::c_int, flags: ::c_int) -> ::c_int;
     pub fn fchmodat(dirfd: ::c_int, pathname: *const ::c_char,
@@ -845,6 +824,39 @@ extern {
     pub fn setns(fd: ::c_int, nstype: ::c_int) -> ::c_int;
     pub fn sem_timedwait(sem: *mut sem_t,
                          abstime: *const ::timespec) -> ::c_int;
+
+    /* Header <fcntl.h> */
+    pub fn openat(dirfd: ::c_int, pathname: *const ::c_char,
+                  flags: ::c_int, ...) -> ::c_int;
+    pub fn posix_fadvise(fd: ::c_int, offset: ::off_t, len: ::off_t,
+                         advise: ::c_int) -> ::c_int;
+    pub fn posix_fallocate(fd: ::c_int, offset: ::off_t,
+                           len: ::off_t) -> ::c_int;
+
+    // Here start non POSIX definitions.
+    pub fn creat64(path: *const c_char, mode: mode_t) -> ::c_int;
+    pub fn open64(path: *const c_char, oflag: ::c_int, ...) -> ::c_int;
+    pub fn openat64(dirfd: ::c_int, pathname: *const ::c_char,
+                    flags: ::c_int, ...) -> ::c_int;
+    pub fn posix_fadvise64(fd: ::c_int, offset: ::off64_t, len: ::off64_t,
+                           advise: ::c_int) -> ::c_int;
+    pub fn posix_fallocate64(fd: ::c_int, offset: ::off64_t,
+                             len: ::off64_t) -> ::c_int;
+
+    pub fn vmsplice(fd: ::c_int,
+                    iov: *const ::iovec,
+                    nr_segs: ::size_t,
+                    flags: ::c_uint) -> ::ssize_t;
+    pub fn splice(fd_in: ::c_int,
+                  off_in: *mut ::loff_t,
+                  fd_out: ::c_int,
+                  off_out: *mut ::loff_t,
+                  len: ::size_t,
+                  flags: ::c_uint) -> ::ssize_t;
+    pub fn tee(fd_in: ::c_int,
+               fd_out: ::c_int,
+               len: ::size_t,
+               flags: ::c_uint) -> ::ssize_t;
 }
 
 cfg_if! {