diff --git a/unix/types_aix.go b/unix/types_aix.go
index 40d2bee..92c03a1 100644
--- a/unix/types_aix.go
+++ b/unix/types_aix.go
@@ -162,6 +162,7 @@
 	SizeofSockaddrUnix     = C.sizeof_struct_sockaddr_un
 	SizeofSockaddrDatalink = C.sizeof_struct_sockaddr_dl
 	SizeofLinger           = C.sizeof_struct_linger
+	SizeofIovec            = C.sizeof_struct_iovec
 	SizeofIPMreq           = C.sizeof_struct_ip_mreq
 	SizeofIPv6Mreq         = C.sizeof_struct_ipv6_mreq
 	SizeofIPv6MTUInfo      = C.sizeof_struct_ip6_mtuinfo
diff --git a/unix/types_dragonfly.go b/unix/types_dragonfly.go
index 6574f6b..53d7731 100644
--- a/unix/types_dragonfly.go
+++ b/unix/types_dragonfly.go
@@ -157,6 +157,7 @@
 	SizeofSockaddrUnix     = C.sizeof_struct_sockaddr_un
 	SizeofSockaddrDatalink = C.sizeof_struct_sockaddr_dl
 	SizeofLinger           = C.sizeof_struct_linger
+	SizeofIovec            = C.sizeof_struct_iovec
 	SizeofIPMreq           = C.sizeof_struct_ip_mreq
 	SizeofIPv6Mreq         = C.sizeof_struct_ipv6_mreq
 	SizeofMsghdr           = C.sizeof_struct_msghdr
diff --git a/unix/types_freebsd.go b/unix/types_freebsd.go
index c6fde42..9be214b 100644
--- a/unix/types_freebsd.go
+++ b/unix/types_freebsd.go
@@ -230,6 +230,7 @@
 	SizeofSockaddrUnix     = C.sizeof_struct_sockaddr_un
 	SizeofSockaddrDatalink = C.sizeof_struct_sockaddr_dl
 	SizeofLinger           = C.sizeof_struct_linger
+	SizeofIovec            = C.sizeof_struct_iovec
 	SizeofIPMreq           = C.sizeof_struct_ip_mreq
 	SizeofIPMreqn          = C.sizeof_struct_ip_mreqn
 	SizeofIPv6Mreq         = C.sizeof_struct_ipv6_mreq
diff --git a/unix/types_netbsd.go b/unix/types_netbsd.go
index 0a81aad..051b0e7 100644
--- a/unix/types_netbsd.go
+++ b/unix/types_netbsd.go
@@ -180,6 +180,7 @@
 	SizeofSockaddrUnix     = C.sizeof_struct_sockaddr_un
 	SizeofSockaddrDatalink = C.sizeof_struct_sockaddr_dl
 	SizeofLinger           = C.sizeof_struct_linger
+	SizeofIovec            = C.sizeof_struct_iovec
 	SizeofIPMreq           = C.sizeof_struct_ip_mreq
 	SizeofIPv6Mreq         = C.sizeof_struct_ipv6_mreq
 	SizeofMsghdr           = C.sizeof_struct_msghdr
diff --git a/unix/types_openbsd.go b/unix/types_openbsd.go
index 775cb57..c49c58e 100644
--- a/unix/types_openbsd.go
+++ b/unix/types_openbsd.go
@@ -159,6 +159,7 @@
 	SizeofSockaddrUnix     = C.sizeof_struct_sockaddr_un
 	SizeofSockaddrDatalink = C.sizeof_struct_sockaddr_dl
 	SizeofLinger           = C.sizeof_struct_linger
+	SizeofIovec            = C.sizeof_struct_iovec
 	SizeofIPMreq           = C.sizeof_struct_ip_mreq
 	SizeofIPv6Mreq         = C.sizeof_struct_ipv6_mreq
 	SizeofMsghdr           = C.sizeof_struct_msghdr
diff --git a/unix/types_solaris.go b/unix/types_solaris.go
index d713f09..8f045bf 100644
--- a/unix/types_solaris.go
+++ b/unix/types_solaris.go
@@ -173,6 +173,7 @@
 	SizeofSockaddrUnix     = C.sizeof_struct_sockaddr_un
 	SizeofSockaddrDatalink = C.sizeof_struct_sockaddr_dl
 	SizeofLinger           = C.sizeof_struct_linger
+	SizeofIovec            = C.sizeof_struct_iovec
 	SizeofIPMreq           = C.sizeof_struct_ip_mreq
 	SizeofIPv6Mreq         = C.sizeof_struct_ipv6_mreq
 	SizeofMsghdr           = C.sizeof_struct_msghdr
diff --git a/unix/ztypes_aix_ppc.go b/unix/ztypes_aix_ppc.go
index 2c1f815..295859c 100644
--- a/unix/ztypes_aix_ppc.go
+++ b/unix/ztypes_aix_ppc.go
@@ -219,6 +219,7 @@
 	SizeofSockaddrUnix     = 0x401
 	SizeofSockaddrDatalink = 0x80
 	SizeofLinger           = 0x8
+	SizeofIovec            = 0x8
 	SizeofIPMreq           = 0x8
 	SizeofIPv6Mreq         = 0x14
 	SizeofIPv6MTUInfo      = 0x20
diff --git a/unix/ztypes_aix_ppc64.go b/unix/ztypes_aix_ppc64.go
index b4a069e..a9ee0ff 100644
--- a/unix/ztypes_aix_ppc64.go
+++ b/unix/ztypes_aix_ppc64.go
@@ -223,6 +223,7 @@
 	SizeofSockaddrUnix     = 0x401
 	SizeofSockaddrDatalink = 0x80
 	SizeofLinger           = 0x8
+	SizeofIovec            = 0x10
 	SizeofIPMreq           = 0x8
 	SizeofIPv6Mreq         = 0x14
 	SizeofIPv6MTUInfo      = 0x20
diff --git a/unix/ztypes_dragonfly_amd64.go b/unix/ztypes_dragonfly_amd64.go
index c4772df..85506a0 100644
--- a/unix/ztypes_dragonfly_amd64.go
+++ b/unix/ztypes_dragonfly_amd64.go
@@ -234,6 +234,7 @@
 	SizeofSockaddrUnix     = 0x6a
 	SizeofSockaddrDatalink = 0x36
 	SizeofLinger           = 0x8
+	SizeofIovec            = 0x10
 	SizeofIPMreq           = 0x8
 	SizeofIPv6Mreq         = 0x14
 	SizeofMsghdr           = 0x30
diff --git a/unix/ztypes_freebsd_386.go b/unix/ztypes_freebsd_386.go
index 2a3ec61..3e9dad3 100644
--- a/unix/ztypes_freebsd_386.go
+++ b/unix/ztypes_freebsd_386.go
@@ -313,6 +313,7 @@
 	SizeofSockaddrUnix     = 0x6a
 	SizeofSockaddrDatalink = 0x36
 	SizeofLinger           = 0x8
+	SizeofIovec            = 0x8
 	SizeofIPMreq           = 0x8
 	SizeofIPMreqn          = 0xc
 	SizeofIPv6Mreq         = 0x14
diff --git a/unix/ztypes_freebsd_amd64.go b/unix/ztypes_freebsd_amd64.go
index e11e954..e00e615 100644
--- a/unix/ztypes_freebsd_amd64.go
+++ b/unix/ztypes_freebsd_amd64.go
@@ -309,6 +309,7 @@
 	SizeofSockaddrUnix     = 0x6a
 	SizeofSockaddrDatalink = 0x36
 	SizeofLinger           = 0x8
+	SizeofIovec            = 0x10
 	SizeofIPMreq           = 0x8
 	SizeofIPMreqn          = 0xc
 	SizeofIPv6Mreq         = 0x14
diff --git a/unix/ztypes_freebsd_arm.go b/unix/ztypes_freebsd_arm.go
index b91c2ae..5da13c8 100644
--- a/unix/ztypes_freebsd_arm.go
+++ b/unix/ztypes_freebsd_arm.go
@@ -311,6 +311,7 @@
 	SizeofSockaddrUnix     = 0x6a
 	SizeofSockaddrDatalink = 0x36
 	SizeofLinger           = 0x8
+	SizeofIovec            = 0x8
 	SizeofIPMreq           = 0x8
 	SizeofIPMreqn          = 0xc
 	SizeofIPv6Mreq         = 0x14
diff --git a/unix/ztypes_freebsd_arm64.go b/unix/ztypes_freebsd_arm64.go
index c6fe1d0..995ecf9 100644
--- a/unix/ztypes_freebsd_arm64.go
+++ b/unix/ztypes_freebsd_arm64.go
@@ -309,6 +309,7 @@
 	SizeofSockaddrUnix     = 0x6a
 	SizeofSockaddrDatalink = 0x36
 	SizeofLinger           = 0x8
+	SizeofIovec            = 0x10
 	SizeofIPMreq           = 0x8
 	SizeofIPMreqn          = 0xc
 	SizeofIPv6Mreq         = 0x14
diff --git a/unix/ztypes_netbsd_386.go b/unix/ztypes_netbsd_386.go
index a89100c..3f11f88 100644
--- a/unix/ztypes_netbsd_386.go
+++ b/unix/ztypes_netbsd_386.go
@@ -248,6 +248,7 @@
 	SizeofSockaddrUnix     = 0x6a
 	SizeofSockaddrDatalink = 0x14
 	SizeofLinger           = 0x8
+	SizeofIovec            = 0x8
 	SizeofIPMreq           = 0x8
 	SizeofIPv6Mreq         = 0x14
 	SizeofMsghdr           = 0x1c
diff --git a/unix/ztypes_netbsd_amd64.go b/unix/ztypes_netbsd_amd64.go
index 289184e..0bed83a 100644
--- a/unix/ztypes_netbsd_amd64.go
+++ b/unix/ztypes_netbsd_amd64.go
@@ -255,6 +255,7 @@
 	SizeofSockaddrUnix     = 0x6a
 	SizeofSockaddrDatalink = 0x14
 	SizeofLinger           = 0x8
+	SizeofIovec            = 0x10
 	SizeofIPMreq           = 0x8
 	SizeofIPv6Mreq         = 0x14
 	SizeofMsghdr           = 0x30
diff --git a/unix/ztypes_netbsd_arm.go b/unix/ztypes_netbsd_arm.go
index 428c450..e4e3bf7 100644
--- a/unix/ztypes_netbsd_arm.go
+++ b/unix/ztypes_netbsd_arm.go
@@ -253,6 +253,7 @@
 	SizeofSockaddrUnix     = 0x6a
 	SizeofSockaddrDatalink = 0x14
 	SizeofLinger           = 0x8
+	SizeofIovec            = 0x8
 	SizeofIPMreq           = 0x8
 	SizeofIPv6Mreq         = 0x14
 	SizeofMsghdr           = 0x1c
diff --git a/unix/ztypes_netbsd_arm64.go b/unix/ztypes_netbsd_arm64.go
index 6f1f284..efac861 100644
--- a/unix/ztypes_netbsd_arm64.go
+++ b/unix/ztypes_netbsd_arm64.go
@@ -255,6 +255,7 @@
 	SizeofSockaddrUnix     = 0x6a
 	SizeofSockaddrDatalink = 0x14
 	SizeofLinger           = 0x8
+	SizeofIovec            = 0x10
 	SizeofIPMreq           = 0x8
 	SizeofIPv6Mreq         = 0x14
 	SizeofMsghdr           = 0x30
diff --git a/unix/ztypes_openbsd_386.go b/unix/ztypes_openbsd_386.go
index 61ea001..80fa295 100644
--- a/unix/ztypes_openbsd_386.go
+++ b/unix/ztypes_openbsd_386.go
@@ -231,6 +231,7 @@
 	SizeofSockaddrUnix     = 0x6a
 	SizeofSockaddrDatalink = 0x20
 	SizeofLinger           = 0x8
+	SizeofIovec            = 0x8
 	SizeofIPMreq           = 0x8
 	SizeofIPv6Mreq         = 0x14
 	SizeofMsghdr           = 0x1c
diff --git a/unix/ztypes_openbsd_amd64.go b/unix/ztypes_openbsd_amd64.go
index 87a493f..560dd6d 100644
--- a/unix/ztypes_openbsd_amd64.go
+++ b/unix/ztypes_openbsd_amd64.go
@@ -235,6 +235,7 @@
 	SizeofSockaddrUnix     = 0x6a
 	SizeofSockaddrDatalink = 0x20
 	SizeofLinger           = 0x8
+	SizeofIovec            = 0x10
 	SizeofIPMreq           = 0x8
 	SizeofIPv6Mreq         = 0x14
 	SizeofMsghdr           = 0x30
diff --git a/unix/ztypes_openbsd_arm.go b/unix/ztypes_openbsd_arm.go
index d80836e..0c1700f 100644
--- a/unix/ztypes_openbsd_arm.go
+++ b/unix/ztypes_openbsd_arm.go
@@ -235,6 +235,7 @@
 	SizeofSockaddrUnix     = 0x6a
 	SizeofSockaddrDatalink = 0x20
 	SizeofLinger           = 0x8
+	SizeofIovec            = 0x8
 	SizeofIPMreq           = 0x8
 	SizeofIPv6Mreq         = 0x14
 	SizeofMsghdr           = 0x1c
diff --git a/unix/ztypes_openbsd_arm64.go b/unix/ztypes_openbsd_arm64.go
index 4e15874..5b3e466 100644
--- a/unix/ztypes_openbsd_arm64.go
+++ b/unix/ztypes_openbsd_arm64.go
@@ -231,6 +231,7 @@
 	SizeofSockaddrUnix     = 0x6a
 	SizeofSockaddrDatalink = 0x20
 	SizeofLinger           = 0x8
+	SizeofIovec            = 0x10
 	SizeofIPMreq           = 0x8
 	SizeofIPv6Mreq         = 0x14
 	SizeofMsghdr           = 0x30
diff --git a/unix/ztypes_openbsd_mips64.go b/unix/ztypes_openbsd_mips64.go
index 992a1f8..62bff16 100644
--- a/unix/ztypes_openbsd_mips64.go
+++ b/unix/ztypes_openbsd_mips64.go
@@ -231,6 +231,7 @@
 	SizeofSockaddrUnix     = 0x6a
 	SizeofSockaddrDatalink = 0x20
 	SizeofLinger           = 0x8
+	SizeofIovec            = 0x10
 	SizeofIPMreq           = 0x8
 	SizeofIPv6Mreq         = 0x14
 	SizeofMsghdr           = 0x30
diff --git a/unix/ztypes_solaris_amd64.go b/unix/ztypes_solaris_amd64.go
index db817f3..ca512af 100644
--- a/unix/ztypes_solaris_amd64.go
+++ b/unix/ztypes_solaris_amd64.go
@@ -234,6 +234,7 @@
 	SizeofSockaddrUnix     = 0x6e
 	SizeofSockaddrDatalink = 0xfc
 	SizeofLinger           = 0x8
+	SizeofIovec            = 0x10
 	SizeofIPMreq           = 0x8
 	SizeofIPv6Mreq         = 0x14
 	SizeofMsghdr           = 0x30