diff --git a/libc-test/semver/freebsd.txt b/libc-test/semver/freebsd.txt
index ed9aceecbd0c2..ffb424e8b508d 100644
--- a/libc-test/semver/freebsd.txt
+++ b/libc-test/semver/freebsd.txt
@@ -785,6 +785,7 @@ MSG_NBIO
 MSG_NOERROR
 MSG_NOSIGNAL
 MSG_NOTIFICATION
+MSG_WAITFORONE
 NANOSECOND
 NETGRAPHDISC
 NET_RT_DUMP
diff --git a/libc-test/semver/openbsd.txt b/libc-test/semver/openbsd.txt
index 090311982c89f..bcd65e09e5792 100644
--- a/libc-test/semver/openbsd.txt
+++ b/libc-test/semver/openbsd.txt
@@ -527,6 +527,7 @@ MSG_CMSG_CLOEXEC
 MSG_DONTWAIT
 MSG_MCAST
 MSG_NOSIGNAL
+MSG_WAITFORONE
 MNT_LAZY
 MNT_NOWAIT
 MNT_WAIT
diff --git a/src/unix/bsd/freebsdlike/freebsd/mod.rs b/src/unix/bsd/freebsdlike/freebsd/mod.rs
index 01a3bf9db8d37..c453e7c9b1c13 100644
--- a/src/unix/bsd/freebsdlike/freebsd/mod.rs
+++ b/src/unix/bsd/freebsdlike/freebsd/mod.rs
@@ -3696,6 +3696,7 @@ pub const MSG_NBIO: ::c_int = 0x00004000;
 pub const MSG_COMPAT: ::c_int = 0x00008000;
 pub const MSG_CMSG_CLOEXEC: ::c_int = 0x00040000;
 pub const MSG_NOSIGNAL: ::c_int = 0x20000;
+pub const MSG_WAITFORONE: ::c_int = 0x00080000;
 
 // utmpx entry types
 pub const EMPTY: ::c_short = 0;
diff --git a/src/unix/bsd/netbsdlike/openbsd/mod.rs b/src/unix/bsd/netbsdlike/openbsd/mod.rs
index 8099bad1d114d..9e9de2e12022d 100644
--- a/src/unix/bsd/netbsdlike/openbsd/mod.rs
+++ b/src/unix/bsd/netbsdlike/openbsd/mod.rs
@@ -1073,6 +1073,8 @@ pub const IP_RECVIF: ::c_int = 30;
 pub const TCP_MD5SIG: ::c_int = 0x04;
 pub const TCP_NOPUSH: ::c_int = 0x10;
 
+pub const MSG_WAITFORONE: ::c_int = 0x1000;
+
 pub const AF_ECMA: ::c_int = 8;
 pub const AF_ROUTE: ::c_int = 17;
 pub const AF_ENCAP: ::c_int = 28;