diff --git a/src/unix/bsd/mod.rs b/src/unix/bsd/mod.rs
index 03ab319269e48b00948a327e8b45c969d8f4e7bf..4379ede364089031ef0717f9f60f6a6130578c8c 100644
--- a/src/unix/bsd/mod.rs
+++ b/src/unix/bsd/mod.rs
@@ -215,6 +215,10 @@ pub const O_NDELAY: ::c_int = O_NONBLOCK;
 pub const F_GETOWN: ::c_int = 5;
 pub const F_SETOWN: ::c_int = 6;
 
+pub const F_RDLCK: ::c_short = 1
+pub const F_UNLCK: ::c_short = 2
+pub const F_WRLCK: ::c_short = 3
+
 pub const MNT_FORCE: ::c_int = 0x80000;
 
 pub const Q_SYNC: ::c_int = 0x600;