diff --git a/src/unix/bsd/netbsdlike/openbsdlike/mod.rs b/src/unix/bsd/netbsdlike/openbsdlike/mod.rs
index d49c94e74c6c17d1d2373d875a0c7d8faccd3849..f75d7b35ac76eaa4657028b6bae5ac5d84fd3512 100644
--- a/src/unix/bsd/netbsdlike/openbsdlike/mod.rs
+++ b/src/unix/bsd/netbsdlike/openbsdlike/mod.rs
@@ -579,6 +579,7 @@ pub const CTL_MACHDEP: ::c_int = 7;
 pub const CTL_DDB: ::c_int = 9;
 pub const CTL_VFS: ::c_int = 10;
 pub const CTL_MAXID: ::c_int = 11;
+pub const HW_NCPUONLINE: ::c_int = 25;
 pub const KERN_OSTYPE: ::c_int = 1;
 pub const KERN_OSRELEASE: ::c_int = 2;
 pub const KERN_OSREV: ::c_int = 3;