unix: add Readv, Writev, Preadv, Pwritev for OpenBSD

Add OpenBSD libc syscall wrappers for vectored I/O, and share the
existing Darwin wrapper implementation and tests.

Fixes golang/go#78049

Change-Id: Ie2743ef36a5cb73b05cc551c9c1108503f5992b6
Reviewed-on: https://go-review.googlesource.com/c/sys/+/771300
LUCI-TryBot-Result: golang-scoped@luci-project-accounts.iam.gserviceaccount.com <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Auto-Submit: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>

unix/readv_unix.go

@@ -0,0 +1,95 @@
+// Copyright 2026 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build darwin || openbsd
+
+package unix
+
+import "unsafe"
+
+// This small allocation gets stack allocated, which lets the
+// common use case of len(iovs) <= minIovec avoid more expensive
+// heap allocations.
+const minIovec = 8
+
+func appendBytes(vecs []Iovec, bs [][]byte) []Iovec {
+	for _, b := range bs {
+		var v Iovec
+		v.SetLen(len(b))
+		if len(b) > 0 {
+			v.Base = &b[0]
+		} else {
+			v.Base = (*byte)(unsafe.Pointer(&_zero))
+		}
+		vecs = append(vecs, v)
+	}
+	return vecs
+}
+
+func writevRacedetect(iovecs []Iovec, n int) {
+	if !raceenabled {
+		return
+	}
+	for i := 0; n > 0 && i < len(iovecs); i++ {
+		m := min(int(iovecs[i].Len), n)
+		n -= m
+		if m > 0 {
+			raceReadRange(unsafe.Pointer(iovecs[i].Base), m)
+		}
+	}
+}
+
+func readvRacedetect(iovecs []Iovec, n int, err error) {
+	if !raceenabled {
+		return
+	}
+	for i := 0; n > 0 && i < len(iovecs); i++ {
+		m := min(int(iovecs[i].Len), n)
+		n -= m
+		if m > 0 {
+			raceWriteRange(unsafe.Pointer(iovecs[i].Base), m)
+		}
+	}
+	if err == nil {
+		raceAcquire(unsafe.Pointer(&ioSync))
+	}
+}
+
+func Readv(fd int, iovs [][]byte) (n int, err error) {
+	iovecs := make([]Iovec, 0, minIovec)
+	iovecs = appendBytes(iovecs, iovs)
+	n, err = readv(fd, iovecs)
+	readvRacedetect(iovecs, n, err)
+	return n, err
+}
+
+func Preadv(fd int, iovs [][]byte, offset int64) (n int, err error) {
+	iovecs := make([]Iovec, 0, minIovec)
+	iovecs = appendBytes(iovecs, iovs)
+	n, err = preadv(fd, iovecs, offset)
+	readvRacedetect(iovecs, n, err)
+	return n, err
+}
+
+func Writev(fd int, iovs [][]byte) (n int, err error) {
+	iovecs := make([]Iovec, 0, minIovec)
+	iovecs = appendBytes(iovecs, iovs)
+	if raceenabled {
+		raceReleaseMerge(unsafe.Pointer(&ioSync))
+	}
+	n, err = writev(fd, iovecs)
+	writevRacedetect(iovecs, n)
+	return n, err
+}
+
+func Pwritev(fd int, iovs [][]byte, offset int64) (n int, err error) {
+	iovecs := make([]Iovec, 0, minIovec)
+	iovecs = appendBytes(iovecs, iovs)
+	if raceenabled {
+		raceReleaseMerge(unsafe.Pointer(&ioSync))
+	}
+	n, err = pwritev(fd, iovecs, offset)
+	writevRacedetect(iovecs, n)
+	return n, err
+}

unix/readv_unix_test.go

@@ -0,0 +1,137 @@
+// Copyright 2026 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build darwin || openbsd
+
+package unix_test
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"golang.org/x/sys/unix"
+)
+
+func TestWritevReadv(t *testing.T) {
+	r, w, err := os.Pipe()
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer r.Close()
+	defer w.Close()
+
+	data := [][]byte{[]byte("hello"), []byte(", "), []byte("world")}
+	wn, err := unix.Writev(int(w.Fd()), data)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if wn != 12 {
+		t.Fatalf("Writev wrote %d bytes, want 12", wn)
+	}
+	w.Close()
+
+	buf1 := make([]byte, 5)
+	buf2 := make([]byte, 2)
+	buf3 := make([]byte, 5)
+	rn, err := unix.Readv(int(r.Fd()), [][]byte{buf1, buf2, buf3})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if rn != 12 {
+		t.Fatalf("Readv read %d bytes, want 12", rn)
+	}
+	if string(buf1) != "hello" || string(buf2) != ", " || string(buf3[:5]) != "world" {
+		t.Fatalf("Readv got %q %q %q, want %q %q %q",
+			buf1, buf2, buf3, "hello", ", ", "world")
+	}
+}
+
+func TestPwritevPreadv(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "preadv_test")
+	f, err := os.Create(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(func() { f.Close() })
+
+	const off = 16
+	data := [][]byte{[]byte("foo"), []byte("bar")}
+	wn, err := unix.Pwritev(int(f.Fd()), data, off)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if wn != 6 {
+		t.Fatalf("Pwritev wrote %d bytes, want 6", wn)
+	}
+
+	got1 := make([]byte, 3)
+	got2 := make([]byte, 3)
+	rn, err := unix.Preadv(int(f.Fd()), [][]byte{got1, got2}, off)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if rn != 6 {
+		t.Fatalf("Preadv read %d bytes, want 6", rn)
+	}
+	if string(got1) != "foo" || string(got2) != "bar" {
+		t.Fatalf("Preadv got %q %q, want %q %q", got1, got2, "foo", "bar")
+	}
+}
+
+func TestPwritevOffset(t *testing.T) {
+	// Regression guard: off_t encoding must not overflow on large offsets.
+	// Mirrors the Linux test for golang.org/issues/57291.
+	path := filepath.Join(t.TempDir(), "offset_test")
+	f, err := os.Create(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(func() { f.Close() })
+
+	const off = 20
+	b := [][]byte{{byte(0)}}
+	n, err := unix.Pwritev(int(f.Fd()), b, off)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if n != 1 {
+		t.Fatalf("Pwritev wrote %d bytes, want 1", n)
+	}
+	info, err := f.Stat()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if want := int64(off + 1); info.Size() != want {
+		t.Fatalf("file size %d, want %d", info.Size(), want)
+	}
+}
+
+func TestWritevReadvAllocations(t *testing.T) {
+	// Verify no heap allocations when iovec count <= minIovec (8).
+	// Allocations in this path indicate a regression in the fast path.
+	f, err := os.Create(filepath.Join(t.TempDir(), "alloc_test"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(func() { f.Close() })
+
+	iovs := make([][]byte, 8)
+	for i := range iovs {
+		iovs[i] = []byte{'A'}
+	}
+
+	check := func(name string, fn func()) {
+		t.Helper()
+		n := int(testing.AllocsPerRun(100, fn))
+		if n != 0 {
+			t.Errorf("%s: got %d allocations, want 0", name, n)
+		}
+	}
+
+	check("Writev", func() { unix.Writev(int(f.Fd()), iovs) })
+	check("Pwritev", func() { unix.Pwritev(int(f.Fd()), iovs, 0) })
+	check("Readv", func() { unix.Readv(int(f.Fd()), iovs) })
+	check("Preadv", func() { unix.Preadv(int(f.Fd()), iovs, 0) })
+}

unix/syscall_darwin.go

@@ -602,95 +602,6 @@ func Connectx(fd int, srcIf uint32, srcAddr, dstAddr Sockaddr, associd SaeAssocI
 	return
 }
 
-const minIovec = 8
-
-func Readv(fd int, iovs [][]byte) (n int, err error) {
-	iovecs := make([]Iovec, 0, minIovec)
-	iovecs = appendBytes(iovecs, iovs)
-	n, err = readv(fd, iovecs)
-	readvRacedetect(iovecs, n, err)
-	return n, err
-}
-
-func Preadv(fd int, iovs [][]byte, offset int64) (n int, err error) {
-	iovecs := make([]Iovec, 0, minIovec)
-	iovecs = appendBytes(iovecs, iovs)
-	n, err = preadv(fd, iovecs, offset)
-	readvRacedetect(iovecs, n, err)
-	return n, err
-}
-
-func Writev(fd int, iovs [][]byte) (n int, err error) {
-	iovecs := make([]Iovec, 0, minIovec)
-	iovecs = appendBytes(iovecs, iovs)
-	if raceenabled {
-		raceReleaseMerge(unsafe.Pointer(&ioSync))
-	}
-	n, err = writev(fd, iovecs)
-	writevRacedetect(iovecs, n)
-	return n, err
-}
-
-func Pwritev(fd int, iovs [][]byte, offset int64) (n int, err error) {
-	iovecs := make([]Iovec, 0, minIovec)
-	iovecs = appendBytes(iovecs, iovs)
-	if raceenabled {
-		raceReleaseMerge(unsafe.Pointer(&ioSync))
-	}
-	n, err = pwritev(fd, iovecs, offset)
-	writevRacedetect(iovecs, n)
-	return n, err
-}
-
-func appendBytes(vecs []Iovec, bs [][]byte) []Iovec {
-	for _, b := range bs {
-		var v Iovec
-		v.SetLen(len(b))
-		if len(b) > 0 {
-			v.Base = &b[0]
-		} else {
-			v.Base = (*byte)(unsafe.Pointer(&_zero))
-		}
-		vecs = append(vecs, v)
-	}
-	return vecs
-}
-
-func writevRacedetect(iovecs []Iovec, n int) {
-	if !raceenabled {
-		return
-	}
-	for i := 0; n > 0 && i < len(iovecs); i++ {
-		m := int(iovecs[i].Len)
-		if m > n {
-			m = n
-		}
-		n -= m
-		if m > 0 {
-			raceReadRange(unsafe.Pointer(iovecs[i].Base), m)
-		}
-	}
-}
-
-func readvRacedetect(iovecs []Iovec, n int, err error) {
-	if !raceenabled {
-		return
-	}
-	for i := 0; n > 0 && i < len(iovecs); i++ {
-		m := int(iovecs[i].Len)
-		if m > n {
-			m = n
-		}
-		n -= m
-		if m > 0 {
-			raceWriteRange(unsafe.Pointer(iovecs[i].Base), m)
-		}
-	}
-	if err == nil {
-		raceAcquire(unsafe.Pointer(&ioSync))
-	}
-}
-
 //sys	connectx(fd int, endpoints *SaEndpoints, associd SaeAssocID, flags uint32, iov []Iovec, n *uintptr, connid *SaeConnID) (err error)
 //sys	sendfile(infd int, outfd int, offset int64, len *int64, hdtr unsafe.Pointer, flags int) (err error)
 

unix/syscall_openbsd.go

@@ -300,6 +300,10 @@ func Uname(uname *Utsname) error {
 //sys	Pathconf(path string, name int) (val int, err error)
 //sys	pread(fd int, p []byte, offset int64) (n int, err error)
 //sys	pwrite(fd int, p []byte, offset int64) (n int, err error)
+//sys	readv(fd int, iovecs []Iovec) (n int, err error)
+//sys	writev(fd int, iovecs []Iovec) (n int, err error)
+//sys	preadv(fd int, iovecs []Iovec, offset int64) (n int, err error)
+//sys	pwritev(fd int, iovecs []Iovec, offset int64) (n int, err error)
 //sys	read(fd int, p []byte) (n int, err error)
 //sys	Readlink(path string, buf []byte) (n int, err error)
 //sys	Readlinkat(dirfd int, path string, buf []byte) (n int, err error)

unix/zsyscall_openbsd_386.go

@@ -1633,6 +1633,90 @@ var libc_pwrite_trampoline_addr uintptr
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func readv(fd int, iovecs []Iovec) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall(libc_readv_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_readv_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_readv readv "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func writev(fd int, iovecs []Iovec) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall(libc_writev_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_writev_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_writev writev "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func preadv(fd int, iovecs []Iovec, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall6(libc_preadv_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)), uintptr(offset), uintptr(offset>>32), 0)
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_preadv_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_preadv preadv "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pwritev(fd int, iovecs []Iovec, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall6(libc_pwritev_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)), uintptr(offset), uintptr(offset>>32), 0)
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_pwritev_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_pwritev pwritev "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func read(fd int, p []byte) (n int, err error) {
 	var _p0 unsafe.Pointer
 	if len(p) > 0 {

unix/zsyscall_openbsd_386.s

@@ -498,6 +498,26 @@ TEXT libc_pwrite_trampoline<>(SB),NOSPLIT,$0-0
 GLOBL	·libc_pwrite_trampoline_addr(SB), RODATA, $4
 DATA	·libc_pwrite_trampoline_addr(SB)/4, $libc_pwrite_trampoline<>(SB)
 
+TEXT libc_readv_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_readv(SB)
+GLOBL	·libc_readv_trampoline_addr(SB), RODATA, $4
+DATA	·libc_readv_trampoline_addr(SB)/4, $libc_readv_trampoline<>(SB)
+
+TEXT libc_writev_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_writev(SB)
+GLOBL	·libc_writev_trampoline_addr(SB), RODATA, $4
+DATA	·libc_writev_trampoline_addr(SB)/4, $libc_writev_trampoline<>(SB)
+
+TEXT libc_preadv_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_preadv(SB)
+GLOBL	·libc_preadv_trampoline_addr(SB), RODATA, $4
+DATA	·libc_preadv_trampoline_addr(SB)/4, $libc_preadv_trampoline<>(SB)
+
+TEXT libc_pwritev_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_pwritev(SB)
+GLOBL	·libc_pwritev_trampoline_addr(SB), RODATA, $4
+DATA	·libc_pwritev_trampoline_addr(SB)/4, $libc_pwritev_trampoline<>(SB)
+
 TEXT libc_read_trampoline<>(SB),NOSPLIT,$0-0
 	JMP	libc_read(SB)
 GLOBL	·libc_read_trampoline_addr(SB), RODATA, $4

unix/zsyscall_openbsd_amd64.go

@@ -1633,6 +1633,90 @@ var libc_pwrite_trampoline_addr uintptr
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func readv(fd int, iovecs []Iovec) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall(libc_readv_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_readv_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_readv readv "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func writev(fd int, iovecs []Iovec) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall(libc_writev_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_writev_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_writev writev "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func preadv(fd int, iovecs []Iovec, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall6(libc_preadv_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)), uintptr(offset), 0, 0)
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_preadv_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_preadv preadv "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pwritev(fd int, iovecs []Iovec, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall6(libc_pwritev_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)), uintptr(offset), 0, 0)
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_pwritev_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_pwritev pwritev "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func read(fd int, p []byte) (n int, err error) {
 	var _p0 unsafe.Pointer
 	if len(p) > 0 {

unix/zsyscall_openbsd_amd64.s

@@ -498,6 +498,26 @@ TEXT libc_pwrite_trampoline<>(SB),NOSPLIT,$0-0
 GLOBL	·libc_pwrite_trampoline_addr(SB), RODATA, $8
 DATA	·libc_pwrite_trampoline_addr(SB)/8, $libc_pwrite_trampoline<>(SB)
 
+TEXT libc_readv_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_readv(SB)
+GLOBL	·libc_readv_trampoline_addr(SB), RODATA, $8
+DATA	·libc_readv_trampoline_addr(SB)/8, $libc_readv_trampoline<>(SB)
+
+TEXT libc_writev_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_writev(SB)
+GLOBL	·libc_writev_trampoline_addr(SB), RODATA, $8
+DATA	·libc_writev_trampoline_addr(SB)/8, $libc_writev_trampoline<>(SB)
+
+TEXT libc_preadv_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_preadv(SB)
+GLOBL	·libc_preadv_trampoline_addr(SB), RODATA, $8
+DATA	·libc_preadv_trampoline_addr(SB)/8, $libc_preadv_trampoline<>(SB)
+
+TEXT libc_pwritev_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_pwritev(SB)
+GLOBL	·libc_pwritev_trampoline_addr(SB), RODATA, $8
+DATA	·libc_pwritev_trampoline_addr(SB)/8, $libc_pwritev_trampoline<>(SB)
+
 TEXT libc_read_trampoline<>(SB),NOSPLIT,$0-0
 	JMP	libc_read(SB)
 GLOBL	·libc_read_trampoline_addr(SB), RODATA, $8

unix/zsyscall_openbsd_arm.go

@@ -1633,6 +1633,90 @@ var libc_pwrite_trampoline_addr uintptr
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func readv(fd int, iovecs []Iovec) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall(libc_readv_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_readv_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_readv readv "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func writev(fd int, iovecs []Iovec) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall(libc_writev_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_writev_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_writev writev "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func preadv(fd int, iovecs []Iovec, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall6(libc_preadv_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)), 0, uintptr(offset), uintptr(offset>>32))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_preadv_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_preadv preadv "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pwritev(fd int, iovecs []Iovec, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall6(libc_pwritev_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)), 0, uintptr(offset), uintptr(offset>>32))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_pwritev_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_pwritev pwritev "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func read(fd int, p []byte) (n int, err error) {
 	var _p0 unsafe.Pointer
 	if len(p) > 0 {

unix/zsyscall_openbsd_arm.s

@@ -498,6 +498,26 @@ TEXT libc_pwrite_trampoline<>(SB),NOSPLIT,$0-0
 GLOBL	·libc_pwrite_trampoline_addr(SB), RODATA, $4
 DATA	·libc_pwrite_trampoline_addr(SB)/4, $libc_pwrite_trampoline<>(SB)
 
+TEXT libc_readv_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_readv(SB)
+GLOBL	·libc_readv_trampoline_addr(SB), RODATA, $4
+DATA	·libc_readv_trampoline_addr(SB)/4, $libc_readv_trampoline<>(SB)
+
+TEXT libc_writev_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_writev(SB)
+GLOBL	·libc_writev_trampoline_addr(SB), RODATA, $4
+DATA	·libc_writev_trampoline_addr(SB)/4, $libc_writev_trampoline<>(SB)
+
+TEXT libc_preadv_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_preadv(SB)
+GLOBL	·libc_preadv_trampoline_addr(SB), RODATA, $4
+DATA	·libc_preadv_trampoline_addr(SB)/4, $libc_preadv_trampoline<>(SB)
+
+TEXT libc_pwritev_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_pwritev(SB)
+GLOBL	·libc_pwritev_trampoline_addr(SB), RODATA, $4
+DATA	·libc_pwritev_trampoline_addr(SB)/4, $libc_pwritev_trampoline<>(SB)
+
 TEXT libc_read_trampoline<>(SB),NOSPLIT,$0-0
 	JMP	libc_read(SB)
 GLOBL	·libc_read_trampoline_addr(SB), RODATA, $4

unix/zsyscall_openbsd_arm64.go

@@ -1633,6 +1633,90 @@ var libc_pwrite_trampoline_addr uintptr
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func readv(fd int, iovecs []Iovec) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall(libc_readv_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_readv_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_readv readv "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func writev(fd int, iovecs []Iovec) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall(libc_writev_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_writev_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_writev writev "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func preadv(fd int, iovecs []Iovec, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall6(libc_preadv_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)), uintptr(offset), 0, 0)
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_preadv_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_preadv preadv "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pwritev(fd int, iovecs []Iovec, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall6(libc_pwritev_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)), uintptr(offset), 0, 0)
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_pwritev_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_pwritev pwritev "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func read(fd int, p []byte) (n int, err error) {
 	var _p0 unsafe.Pointer
 	if len(p) > 0 {

unix/zsyscall_openbsd_arm64.s

@@ -498,6 +498,26 @@ TEXT libc_pwrite_trampoline<>(SB),NOSPLIT,$0-0
 GLOBL	·libc_pwrite_trampoline_addr(SB), RODATA, $8
 DATA	·libc_pwrite_trampoline_addr(SB)/8, $libc_pwrite_trampoline<>(SB)
 
+TEXT libc_readv_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_readv(SB)
+GLOBL	·libc_readv_trampoline_addr(SB), RODATA, $8
+DATA	·libc_readv_trampoline_addr(SB)/8, $libc_readv_trampoline<>(SB)
+
+TEXT libc_writev_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_writev(SB)
+GLOBL	·libc_writev_trampoline_addr(SB), RODATA, $8
+DATA	·libc_writev_trampoline_addr(SB)/8, $libc_writev_trampoline<>(SB)
+
+TEXT libc_preadv_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_preadv(SB)
+GLOBL	·libc_preadv_trampoline_addr(SB), RODATA, $8
+DATA	·libc_preadv_trampoline_addr(SB)/8, $libc_preadv_trampoline<>(SB)
+
+TEXT libc_pwritev_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_pwritev(SB)
+GLOBL	·libc_pwritev_trampoline_addr(SB), RODATA, $8
+DATA	·libc_pwritev_trampoline_addr(SB)/8, $libc_pwritev_trampoline<>(SB)
+
 TEXT libc_read_trampoline<>(SB),NOSPLIT,$0-0
 	JMP	libc_read(SB)
 GLOBL	·libc_read_trampoline_addr(SB), RODATA, $8

unix/zsyscall_openbsd_mips64.go

@@ -1633,6 +1633,90 @@ var libc_pwrite_trampoline_addr uintptr
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func readv(fd int, iovecs []Iovec) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall(libc_readv_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_readv_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_readv readv "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func writev(fd int, iovecs []Iovec) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall(libc_writev_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_writev_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_writev writev "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func preadv(fd int, iovecs []Iovec, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall6(libc_preadv_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)), uintptr(offset), 0, 0)
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_preadv_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_preadv preadv "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pwritev(fd int, iovecs []Iovec, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall6(libc_pwritev_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)), uintptr(offset), 0, 0)
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_pwritev_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_pwritev pwritev "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func read(fd int, p []byte) (n int, err error) {
 	var _p0 unsafe.Pointer
 	if len(p) > 0 {

unix/zsyscall_openbsd_mips64.s

@@ -498,6 +498,26 @@ TEXT libc_pwrite_trampoline<>(SB),NOSPLIT,$0-0
 GLOBL	·libc_pwrite_trampoline_addr(SB), RODATA, $8
 DATA	·libc_pwrite_trampoline_addr(SB)/8, $libc_pwrite_trampoline<>(SB)
 
+TEXT libc_readv_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_readv(SB)
+GLOBL	·libc_readv_trampoline_addr(SB), RODATA, $8
+DATA	·libc_readv_trampoline_addr(SB)/8, $libc_readv_trampoline<>(SB)
+
+TEXT libc_writev_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_writev(SB)
+GLOBL	·libc_writev_trampoline_addr(SB), RODATA, $8
+DATA	·libc_writev_trampoline_addr(SB)/8, $libc_writev_trampoline<>(SB)
+
+TEXT libc_preadv_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_preadv(SB)
+GLOBL	·libc_preadv_trampoline_addr(SB), RODATA, $8
+DATA	·libc_preadv_trampoline_addr(SB)/8, $libc_preadv_trampoline<>(SB)
+
+TEXT libc_pwritev_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_pwritev(SB)
+GLOBL	·libc_pwritev_trampoline_addr(SB), RODATA, $8
+DATA	·libc_pwritev_trampoline_addr(SB)/8, $libc_pwritev_trampoline<>(SB)
+
 TEXT libc_read_trampoline<>(SB),NOSPLIT,$0-0
 	JMP	libc_read(SB)
 GLOBL	·libc_read_trampoline_addr(SB), RODATA, $8

unix/zsyscall_openbsd_ppc64.go

@@ -1633,6 +1633,90 @@ var libc_pwrite_trampoline_addr uintptr
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func readv(fd int, iovecs []Iovec) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall(libc_readv_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_readv_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_readv readv "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func writev(fd int, iovecs []Iovec) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall(libc_writev_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_writev_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_writev writev "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func preadv(fd int, iovecs []Iovec, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall6(libc_preadv_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)), uintptr(offset), 0, 0)
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_preadv_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_preadv preadv "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pwritev(fd int, iovecs []Iovec, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall6(libc_pwritev_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)), uintptr(offset), 0, 0)
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_pwritev_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_pwritev pwritev "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func read(fd int, p []byte) (n int, err error) {
 	var _p0 unsafe.Pointer
 	if len(p) > 0 {

unix/zsyscall_openbsd_ppc64.s

@@ -597,6 +597,30 @@ TEXT libc_pwrite_trampoline<>(SB),NOSPLIT,$0-0
 GLOBL	·libc_pwrite_trampoline_addr(SB), RODATA, $8
 DATA	·libc_pwrite_trampoline_addr(SB)/8, $libc_pwrite_trampoline<>(SB)
 
+TEXT libc_readv_trampoline<>(SB),NOSPLIT,$0-0
+	CALL	libc_readv(SB)
+	RET
+GLOBL	·libc_readv_trampoline_addr(SB), RODATA, $8
+DATA	·libc_readv_trampoline_addr(SB)/8, $libc_readv_trampoline<>(SB)
+
+TEXT libc_writev_trampoline<>(SB),NOSPLIT,$0-0
+	CALL	libc_writev(SB)
+	RET
+GLOBL	·libc_writev_trampoline_addr(SB), RODATA, $8
+DATA	·libc_writev_trampoline_addr(SB)/8, $libc_writev_trampoline<>(SB)
+
+TEXT libc_preadv_trampoline<>(SB),NOSPLIT,$0-0
+	CALL	libc_preadv(SB)
+	RET
+GLOBL	·libc_preadv_trampoline_addr(SB), RODATA, $8
+DATA	·libc_preadv_trampoline_addr(SB)/8, $libc_preadv_trampoline<>(SB)
+
+TEXT libc_pwritev_trampoline<>(SB),NOSPLIT,$0-0
+	CALL	libc_pwritev(SB)
+	RET
+GLOBL	·libc_pwritev_trampoline_addr(SB), RODATA, $8
+DATA	·libc_pwritev_trampoline_addr(SB)/8, $libc_pwritev_trampoline<>(SB)
+
 TEXT libc_read_trampoline<>(SB),NOSPLIT,$0-0
 	CALL	libc_read(SB)
 	RET

unix/zsyscall_openbsd_riscv64.go

@@ -1633,6 +1633,90 @@ var libc_pwrite_trampoline_addr uintptr
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func readv(fd int, iovecs []Iovec) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall(libc_readv_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_readv_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_readv readv "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func writev(fd int, iovecs []Iovec) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall(libc_writev_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_writev_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_writev writev "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func preadv(fd int, iovecs []Iovec, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall6(libc_preadv_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)), uintptr(offset), 0, 0)
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_preadv_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_preadv preadv "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pwritev(fd int, iovecs []Iovec, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall_syscall6(libc_pwritev_trampoline_addr, uintptr(fd), uintptr(_p0), uintptr(len(iovecs)), uintptr(offset), 0, 0)
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_pwritev_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_pwritev pwritev "libc.so"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func read(fd int, p []byte) (n int, err error) {
 	var _p0 unsafe.Pointer
 	if len(p) > 0 {

unix/zsyscall_openbsd_riscv64.s

@@ -498,6 +498,26 @@ TEXT libc_pwrite_trampoline<>(SB),NOSPLIT,$0-0
 GLOBL	·libc_pwrite_trampoline_addr(SB), RODATA, $8
 DATA	·libc_pwrite_trampoline_addr(SB)/8, $libc_pwrite_trampoline<>(SB)
 
+TEXT libc_readv_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_readv(SB)
+GLOBL	·libc_readv_trampoline_addr(SB), RODATA, $8
+DATA	·libc_readv_trampoline_addr(SB)/8, $libc_readv_trampoline<>(SB)
+
+TEXT libc_writev_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_writev(SB)
+GLOBL	·libc_writev_trampoline_addr(SB), RODATA, $8
+DATA	·libc_writev_trampoline_addr(SB)/8, $libc_writev_trampoline<>(SB)
+
+TEXT libc_preadv_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_preadv(SB)
+GLOBL	·libc_preadv_trampoline_addr(SB), RODATA, $8
+DATA	·libc_preadv_trampoline_addr(SB)/8, $libc_preadv_trampoline<>(SB)
+
+TEXT libc_pwritev_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_pwritev(SB)
+GLOBL	·libc_pwritev_trampoline_addr(SB), RODATA, $8
+DATA	·libc_pwritev_trampoline_addr(SB)/8, $libc_pwritev_trampoline<>(SB)
+
 TEXT libc_read_trampoline<>(SB),NOSPLIT,$0-0
 	JMP	libc_read(SB)
 GLOBL	·libc_read_trampoline_addr(SB), RODATA, $8