all: update to use os.ReadFile, os.WriteFile, os.CreateTemp, os.MkdirTemp

As part of #42026, these helpers from io/ioutil were moved to os.
(ioutil.TempFile and TempDir became os.CreateTemp and MkdirTemp.)

Update the Go tree to use the preferred names.

As usual, code compiled with the Go 1.4 bootstrap toolchain
and code vendored from other sources is excluded.

ReadDir changes are in a separate CL, because they are not a
simple search and replace.

For #42026.

Change-Id: If318df0216d57e95ea0c4093b89f65e5b0ababb3
Reviewed-on: https://go-review.googlesource.com/c/go/+/266365
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

27 files changed, 67 insertions, 88 deletions

diff --git a/src/runtime/crash_test.go b/src/runtime/crash_test.go
index 5e22b7593e..58ad4f3eba 100644
--- a/src/runtime/crash_test.go
+++ b/src/runtime/crash_test.go
@@ -9,7 +9,6 @@ import (
 	"flag"
 	"fmt"
 	"internal/testenv"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -117,7 +116,7 @@ func buildTestProg(t *testing.T, binary string, flags ...string) (string, error)
 	testprog.Lock()
 	defer testprog.Unlock()
 	if testprog.dir == "" {
-		dir, err := ioutil.TempDir("", "go-build")
+		dir, err := os.MkdirTemp("", "go-build")
 		if err != nil {
 			t.Fatalf("failed to create temp directory: %v", err)
 		}
diff --git a/src/runtime/crash_unix_test.go b/src/runtime/crash_unix_test.go
index ebbdbfe5b9..803b031873 100644
--- a/src/runtime/crash_unix_test.go
+++ b/src/runtime/crash_unix_test.go
@@ -10,7 +10,6 @@ import (
 	"bytes"
 	"internal/testenv"
 	"io"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -85,13 +84,13 @@ func TestCrashDumpsAllThreads(t *testing.T) {
 
 	t.Parallel()
 
-	dir, err := ioutil.TempDir("", "go-build")
+	dir, err := os.MkdirTemp("", "go-build")
 	if err != nil {
 		t.Fatalf("failed to create temp directory: %v", err)
 	}
 	defer os.RemoveAll(dir)
 
-	if err := ioutil.WriteFile(filepath.Join(dir, "main.go"), []byte(crashDumpsAllThreadsSource), 0666); err != nil {
+	if err := os.WriteFile(filepath.Join(dir, "main.go"), []byte(crashDumpsAllThreadsSource), 0666); err != nil {
 		t.Fatalf("failed to create Go file: %v", err)
 	}
 
diff --git a/src/runtime/debug/heapdump_test.go b/src/runtime/debug/heapdump_test.go
index de1ec27d21..768934d05d 100644
--- a/src/runtime/debug/heapdump_test.go
+++ b/src/runtime/debug/heapdump_test.go
@@ -5,7 +5,6 @@
 package debug_test
 
 import (
-	"io/ioutil"
 	"os"
 	"runtime"
 	. "runtime/debug"
@@ -16,7 +15,7 @@ func TestWriteHeapDumpNonempty(t *testing.T) {
 	if runtime.GOOS == "js" {
 		t.Skipf("WriteHeapDump is not available on %s.", runtime.GOOS)
 	}
-	f, err := ioutil.TempFile("", "heapdumptest")
+	f, err := os.CreateTemp("", "heapdumptest")
 	if err != nil {
 		t.Fatalf("TempFile failed: %v", err)
 	}
@@ -45,7 +44,7 @@ func TestWriteHeapDumpFinalizers(t *testing.T) {
 	if runtime.GOOS == "js" {
 		t.Skipf("WriteHeapDump is not available on %s.", runtime.GOOS)
 	}
-	f, err := ioutil.TempFile("", "heapdumptest")
+	f, err := os.CreateTemp("", "heapdumptest")
 	if err != nil {
 		t.Fatalf("TempFile failed: %v", err)
 	}
diff --git a/src/runtime/debug_test.go b/src/runtime/debug_test.go
index 722e81121f..a0b3f84382 100644
--- a/src/runtime/debug_test.go
+++ b/src/runtime/debug_test.go
@@ -17,7 +17,7 @@ package runtime_test
 
 import (
 	"fmt"
-	"io/ioutil"
+	"os"
 	"regexp"
 	"runtime"
 	"runtime/debug"
@@ -95,7 +95,7 @@ func debugCallTKill(tid int) error {
 // Linux-specific.
 func skipUnderDebugger(t *testing.T) {
 	pid := syscall.Getpid()
-	status, err := ioutil.ReadFile(fmt.Sprintf("/proc/%d/status", pid))
+	status, err := os.ReadFile(fmt.Sprintf("/proc/%d/status", pid))
 	if err != nil {
 		t.Logf("couldn't get proc tracer: %s", err)
 		return
diff --git a/src/runtime/env_plan9.go b/src/runtime/env_plan9.go
index b7ea863735..f1ac4760a7 100644
--- a/src/runtime/env_plan9.go
+++ b/src/runtime/env_plan9.go
@@ -23,8 +23,8 @@ const (
 // to the (possibly shared) Plan 9 environment, so that Setenv and Getenv
 // conform to the same Posix semantics as on other operating systems.
 // For Plan 9 shared environment semantics, instead of Getenv(key) and
-// Setenv(key, value), one can use ioutil.ReadFile("/env/" + key) and
-// ioutil.WriteFile("/env/" + key, value, 0666) respectively.
+// Setenv(key, value), one can use os.ReadFile("/env/" + key) and
+// os.WriteFile("/env/" + key, value, 0666) respectively.
 //go:nosplit
 func goenvs() {
 	buf := make([]byte, envBufSize)
diff --git a/src/runtime/internal/sys/gengoos.go b/src/runtime/internal/sys/gengoos.go
index 2a4bf0c3b4..9bbc48d94f 100644
--- a/src/runtime/internal/sys/gengoos.go
+++ b/src/runtime/internal/sys/gengoos.go
@@ -9,8 +9,8 @@ package main
 import (
 	"bytes"
 	"fmt"
-	"io/ioutil"
 	"log"
+	"os"
 	"strconv"
 	"strings"
 )
@@ -18,7 +18,7 @@ import (
 var gooses, goarches []string
 
 func main() {
-	data, err := ioutil.ReadFile("../../../go/build/syslist.go")
+	data, err := os.ReadFile("../../../go/build/syslist.go")
 	if err != nil {
 		log.Fatal(err)
 	}
@@ -68,7 +68,7 @@ func main() {
 			}
 			fmt.Fprintf(&buf, "const Goos%s = %d\n", strings.Title(goos), value)
 		}
-		err := ioutil.WriteFile("zgoos_"+target+".go", buf.Bytes(), 0666)
+		err := os.WriteFile("zgoos_"+target+".go", buf.Bytes(), 0666)
 		if err != nil {
 			log.Fatal(err)
 		}
@@ -90,7 +90,7 @@ func main() {
 			}
 			fmt.Fprintf(&buf, "const Goarch%s = %d\n", strings.Title(goarch), value)
 		}
-		err := ioutil.WriteFile("zgoarch_"+target+".go", buf.Bytes(), 0666)
+		err := os.WriteFile("zgoarch_"+target+".go", buf.Bytes(), 0666)
 		if err != nil {
 			log.Fatal(err)
 		}
diff --git a/src/runtime/memmove_linux_amd64_test.go b/src/runtime/memmove_linux_amd64_test.go
index d0e8b42a5a..b3ccd907b9 100644
--- a/src/runtime/memmove_linux_amd64_test.go
+++ b/src/runtime/memmove_linux_amd64_test.go
@@ -5,7 +5,6 @@
 package runtime_test
 
 import (
-	"io/ioutil"
 	"os"
 	"reflect"
 	"syscall"
@@ -18,7 +17,7 @@ import (
 func TestMemmoveOverflow(t *testing.T) {
 	t.Parallel()
 	// Create a temporary file.
-	tmp, err := ioutil.TempFile("", "go-memmovetest")
+	tmp, err := os.CreateTemp("", "go-memmovetest")
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/src/runtime/mkduff.go b/src/runtime/mkduff.go
index 6ddf0256e9..94ae75fbfe 100644
--- a/src/runtime/mkduff.go
+++ b/src/runtime/mkduff.go
@@ -27,8 +27,8 @@ import (
 	"bytes"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"log"
+	"os"
 )
 
 func main() {
@@ -54,7 +54,7 @@ func gen(arch string, tags, zero, copy func(io.Writer)) {
 	fmt.Fprintln(&buf)
 	copy(&buf)
 
-	if err := ioutil.WriteFile("duff_"+arch+".s", buf.Bytes(), 0644); err != nil {
+	if err := os.WriteFile("duff_"+arch+".s", buf.Bytes(), 0644); err != nil {
 		log.Fatalln(err)
 	}
 }
diff --git a/src/runtime/mkfastlog2table.go b/src/runtime/mkfastlog2table.go
index 305c84a7c1..d650292394 100644
--- a/src/runtime/mkfastlog2table.go
+++ b/src/runtime/mkfastlog2table.go
@@ -12,9 +12,9 @@ package main
 import (
 	"bytes"
 	"fmt"
-	"io/ioutil"
 	"log"
 	"math"
+	"os"
 )
 
 func main() {
@@ -36,7 +36,7 @@ func main() {
 	}
 	fmt.Fprintln(&buf, "}")
 
-	if err := ioutil.WriteFile("fastlog2table.go", buf.Bytes(), 0644); err != nil {
+	if err := os.WriteFile("fastlog2table.go", buf.Bytes(), 0644); err != nil {
 		log.Fatalln(err)
 	}
 }
diff --git a/src/runtime/mksizeclasses.go b/src/runtime/mksizeclasses.go
index 1a210953a4..b92d1fed5f 100644
--- a/src/runtime/mksizeclasses.go
+++ b/src/runtime/mksizeclasses.go
@@ -35,7 +35,6 @@ import (
 	"fmt"
 	"go/format"
 	"io"
-	"io/ioutil"
 	"log"
 	"os"
 )
@@ -65,7 +64,7 @@ func main() {
 	if *stdout {
 		_, err = os.Stdout.Write(out)
 	} else {
-		err = ioutil.WriteFile("sizeclasses.go", out, 0666)
+		err = os.WriteFile("sizeclasses.go", out, 0666)
 	}
 	if err != nil {
 		log.Fatal(err)
diff --git a/src/runtime/pprof/pprof_test.go b/src/runtime/pprof/pprof_test.go
index b807072485..b6ee160e84 100644
--- a/src/runtime/pprof/pprof_test.go
+++ b/src/runtime/pprof/pprof_test.go
@@ -13,7 +13,6 @@ import (
 	"internal/profile"
 	"internal/testenv"
 	"io"
-	"io/ioutil"
 	"math/big"
 	"os"
 	"os/exec"
@@ -1179,7 +1178,7 @@ func TestLabelRace(t *testing.T) {
 // Check that there is no deadlock when the program receives SIGPROF while in
 // 64bit atomics' critical section. Used to happen on mips{,le}. See #20146.
 func TestAtomicLoadStore64(t *testing.T) {
-	f, err := ioutil.TempFile("", "profatomic")
+	f, err := os.CreateTemp("", "profatomic")
 	if err != nil {
 		t.Fatalf("TempFile: %v", err)
 	}
@@ -1208,7 +1207,7 @@ func TestAtomicLoadStore64(t *testing.T) {
 func TestTracebackAll(t *testing.T) {
 	// With gccgo, if a profiling signal arrives at the wrong time
 	// during traceback, it may crash or hang. See issue #29448.
-	f, err := ioutil.TempFile("", "proftraceback")
+	f, err := os.CreateTemp("", "proftraceback")
 	if err != nil {
 		t.Fatalf("TempFile: %v", err)
 	}
diff --git a/src/runtime/pprof/proto.go b/src/runtime/pprof/proto.go
index 8519af6985..bdb4454b6e 100644
--- a/src/runtime/pprof/proto.go
+++ b/src/runtime/pprof/proto.go
@@ -9,7 +9,7 @@ import (
 	"compress/gzip"
 	"fmt"
 	"io"
-	"io/ioutil"
+	"os"
 	"runtime"
 	"strconv"
 	"time"
@@ -575,7 +575,7 @@ func (b *profileBuilder) emitLocation() uint64 {
 // It saves the address ranges of the mappings in b.mem for use
 // when emitting locations.
 func (b *profileBuilder) readMapping() {
-	data, _ := ioutil.ReadFile("/proc/self/maps")
+	data, _ := os.ReadFile("/proc/self/maps")
 	parseProcSelfMaps(data, b.addMapping)
 	if len(b.mem) == 0 { // pprof expects a map entry, so fake one.
 		b.addMappingEntry(0, 0, 0, "", "", true)
diff --git a/src/runtime/pprof/proto_test.go b/src/runtime/pprof/proto_test.go
index 3043d5353f..5eb1aab140 100644
--- a/src/runtime/pprof/proto_test.go
+++ b/src/runtime/pprof/proto_test.go
@@ -10,7 +10,6 @@ import (
 	"fmt"
 	"internal/profile"
 	"internal/testenv"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"reflect"
@@ -78,7 +77,7 @@ func testPCs(t *testing.T) (addr1, addr2 uint64, map1, map2 *profile.Mapping) {
 	switch runtime.GOOS {
 	case "linux", "android", "netbsd":
 		// Figure out two addresses from /proc/self/maps.
-		mmap, err := ioutil.ReadFile("/proc/self/maps")
+		mmap, err := os.ReadFile("/proc/self/maps")
 		if err != nil {
 			t.Fatal(err)
 		}
diff --git a/src/runtime/race/output_test.go b/src/runtime/race/output_test.go
index 5d0192f67f..986667332f 100644
--- a/src/runtime/race/output_test.go
+++ b/src/runtime/race/output_test.go
@@ -8,7 +8,6 @@ package race_test
 
 import (
 	"internal/testenv"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -19,7 +18,7 @@ import (
 )
 
 func TestOutput(t *testing.T) {
-	pkgdir, err := ioutil.TempDir("", "go-build-race-output")
+	pkgdir, err := os.MkdirTemp("", "go-build-race-output")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -34,7 +33,7 @@ func TestOutput(t *testing.T) {
 			t.Logf("test %v runs only on %v, skipping: ", test.name, test.goos)
 			continue
 		}
-		dir, err := ioutil.TempDir("", "go-build")
+		dir, err := os.MkdirTemp("", "go-build")
 		if err != nil {
 			t.Fatalf("failed to create temp directory: %v", err)
 		}
diff --git a/src/runtime/race/testdata/io_test.go b/src/runtime/race/testdata/io_test.go
index 30a121bee4..c5055f7837 100644
--- a/src/runtime/race/testdata/io_test.go
+++ b/src/runtime/race/testdata/io_test.go
@@ -6,7 +6,6 @@ package race_test
 
 import (
 	"fmt"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"os"
@@ -18,7 +17,7 @@ import (
 
 func TestNoRaceIOFile(t *testing.T) {
 	x := 0
-	path, _ := ioutil.TempDir("", "race_test")
+	path, _ := os.MkdirTemp("", "race_test")
 	fname := filepath.Join(path, "data")
 	go func() {
 		x = 42
diff --git a/src/runtime/runtime-gdb_test.go b/src/runtime/runtime-gdb_test.go
index e52bd1c4c4..5df8c3c745 100644
--- a/src/runtime/runtime-gdb_test.go
+++ b/src/runtime/runtime-gdb_test.go
@@ -8,7 +8,6 @@ import (
 	"bytes"
 	"fmt"
 	"internal/testenv"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -170,7 +169,7 @@ func testGdbPython(t *testing.T, cgo bool) {
 	checkGdbVersion(t)
 	checkGdbPython(t)
 
-	dir, err := ioutil.TempDir("", "go-build")
+	dir, err := os.MkdirTemp("", "go-build")
 	if err != nil {
 		t.Fatalf("failed to create temp directory: %v", err)
 	}
@@ -195,7 +194,7 @@ func testGdbPython(t *testing.T, cgo bool) {
 		}
 	}
 
-	err = ioutil.WriteFile(filepath.Join(dir, "main.go"), src, 0644)
+	err = os.WriteFile(filepath.Join(dir, "main.go"), src, 0644)
 	if err != nil {
 		t.Fatalf("failed to create file: %v", err)
 	}
@@ -404,7 +403,7 @@ func TestGdbBacktrace(t *testing.T) {
 	t.Parallel()
 	checkGdbVersion(t)
 
-	dir, err := ioutil.TempDir("", "go-build")
+	dir, err := os.MkdirTemp("", "go-build")
 	if err != nil {
 		t.Fatalf("failed to create temp directory: %v", err)
 	}
@@ -412,7 +411,7 @@ func TestGdbBacktrace(t *testing.T) {
 
 	// Build the source code.
 	src := filepath.Join(dir, "main.go")
-	err = ioutil.WriteFile(src, []byte(backtraceSource), 0644)
+	err = os.WriteFile(src, []byte(backtraceSource), 0644)
 	if err != nil {
 		t.Fatalf("failed to create file: %v", err)
 	}
@@ -482,7 +481,7 @@ func TestGdbAutotmpTypes(t *testing.T) {
 		t.Skip("TestGdbAutotmpTypes is too slow on aix/ppc64")
 	}
 
-	dir, err := ioutil.TempDir("", "go-build")
+	dir, err := os.MkdirTemp("", "go-build")
 	if err != nil {
 		t.Fatalf("failed to create temp directory: %v", err)
 	}
@@ -490,7 +489,7 @@ func TestGdbAutotmpTypes(t *testing.T) {
 
 	// Build the source code.
 	src := filepath.Join(dir, "main.go")
-	err = ioutil.WriteFile(src, []byte(autotmpTypeSource), 0644)
+	err = os.WriteFile(src, []byte(autotmpTypeSource), 0644)
 	if err != nil {
 		t.Fatalf("failed to create file: %v", err)
 	}
@@ -551,7 +550,7 @@ func TestGdbConst(t *testing.T) {
 	t.Parallel()
 	checkGdbVersion(t)
 
-	dir, err := ioutil.TempDir("", "go-build")
+	dir, err := os.MkdirTemp("", "go-build")
 	if err != nil {
 		t.Fatalf("failed to create temp directory: %v", err)
 	}
@@ -559,7 +558,7 @@ func TestGdbConst(t *testing.T) {
 
 	// Build the source code.
 	src := filepath.Join(dir, "main.go")
-	err = ioutil.WriteFile(src, []byte(constsSource), 0644)
+	err = os.WriteFile(src, []byte(constsSource), 0644)
 	if err != nil {
 		t.Fatalf("failed to create file: %v", err)
 	}
@@ -618,7 +617,7 @@ func TestGdbPanic(t *testing.T) {
 	t.Parallel()
 	checkGdbVersion(t)
 
-	dir, err := ioutil.TempDir("", "go-build")
+	dir, err := os.MkdirTemp("", "go-build")
 	if err != nil {
 		t.Fatalf("failed to create temp directory: %v", err)
 	}
@@ -626,7 +625,7 @@ func TestGdbPanic(t *testing.T) {
 
 	// Build the source code.
 	src := filepath.Join(dir, "main.go")
-	err = ioutil.WriteFile(src, []byte(panicSource), 0644)
+	err = os.WriteFile(src, []byte(panicSource), 0644)
 	if err != nil {
 		t.Fatalf("failed to create file: %v", err)
 	}
@@ -696,7 +695,7 @@ func TestGdbInfCallstack(t *testing.T) {
 	t.Parallel()
 	checkGdbVersion(t)
 
-	dir, err := ioutil.TempDir("", "go-build")
+	dir, err := os.MkdirTemp("", "go-build")
 	if err != nil {
 		t.Fatalf("failed to create temp directory: %v", err)
 	}
@@ -704,7 +703,7 @@ func TestGdbInfCallstack(t *testing.T) {
 
 	// Build the source code.
 	src := filepath.Join(dir, "main.go")
-	err = ioutil.WriteFile(src, []byte(InfCallstackSource), 0644)
+	err = os.WriteFile(src, []byte(InfCallstackSource), 0644)
 	if err != nil {
 		t.Fatalf("failed to create file: %v", err)
 	}
diff --git a/src/runtime/runtime-lldb_test.go b/src/runtime/runtime-lldb_test.go
index 1e2e5d5be9..c923b872aa 100644
--- a/src/runtime/runtime-lldb_test.go
+++ b/src/runtime/runtime-lldb_test.go
@@ -6,7 +6,6 @@ package runtime_test
 
 import (
 	"internal/testenv"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -143,20 +142,20 @@ func TestLldbPython(t *testing.T) {
 
 	checkLldbPython(t)
 
-	dir, err := ioutil.TempDir("", "go-build")
+	dir, err := os.MkdirTemp("", "go-build")
 	if err != nil {
 		t.Fatalf("failed to create temp directory: %v", err)
 	}
 	defer os.RemoveAll(dir)
 
 	src := filepath.Join(dir, "main.go")
-	err = ioutil.WriteFile(src, []byte(lldbHelloSource), 0644)
+	err = os.WriteFile(src, []byte(lldbHelloSource), 0644)
 	if err != nil {
 		t.Fatalf("failed to create src file: %v", err)
 	}
 
 	mod := filepath.Join(dir, "go.mod")
-	err = ioutil.WriteFile(mod, []byte("module lldbtest"), 0644)
+	err = os.WriteFile(mod, []byte("module lldbtest"), 0644)
 	if err != nil {
 		t.Fatalf("failed to create mod file: %v", err)
 	}
@@ -172,7 +171,7 @@ func TestLldbPython(t *testing.T) {
 	}
 
 	src = filepath.Join(dir, "script.py")
-	err = ioutil.WriteFile(src, []byte(lldbScriptSource), 0755)
+	err = os.WriteFile(src, []byte(lldbScriptSource), 0755)
 	if err != nil {
 		t.Fatalf("failed to create script: %v", err)
 	}
diff --git a/src/runtime/signal_windows_test.go b/src/runtime/signal_windows_test.go
index f99857193c..a5a885c2f7 100644
--- a/src/runtime/signal_windows_test.go
+++ b/src/runtime/signal_windows_test.go
@@ -7,7 +7,6 @@ import (
 	"bytes"
 	"fmt"
 	"internal/testenv"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -28,7 +27,7 @@ func TestVectoredHandlerDontCrashOnLibrary(t *testing.T) {
 	testenv.MustHaveExecPath(t, "gcc")
 	testprog.Lock()
 	defer testprog.Unlock()
-	dir, err := ioutil.TempDir("", "go-build")
+	dir, err := os.MkdirTemp("", "go-build")
 	if err != nil {
 		t.Fatalf("failed to create temp directory: %v", err)
 	}
@@ -93,7 +92,7 @@ func TestLibraryCtrlHandler(t *testing.T) {
 	testenv.MustHaveExecPath(t, "gcc")
 	testprog.Lock()
 	defer testprog.Unlock()
-	dir, err := ioutil.TempDir("", "go-build")
+	dir, err := os.MkdirTemp("", "go-build")
 	if err != nil {
 		t.Fatalf("failed to create temp directory: %v", err)
 	}
diff --git a/src/runtime/syscall_windows_test.go b/src/runtime/syscall_windows_test.go
index a20573eb6a..fb215b3c31 100644
--- a/src/runtime/syscall_windows_test.go
+++ b/src/runtime/syscall_windows_test.go
@@ -10,7 +10,6 @@ import (
 	"internal/syscall/windows/sysdll"
 	"internal/testenv"
 	"io"
-	"io/ioutil"
 	"math"
 	"os"
 	"os/exec"
@@ -446,7 +445,7 @@ func TestStdcallAndCDeclCallbacks(t *testing.T) {
 	if _, err := exec.LookPath("gcc"); err != nil {
 		t.Skip("skipping test: gcc is missing")
 	}
-	tmp, err := ioutil.TempDir("", "TestCDeclCallback")
+	tmp, err := os.MkdirTemp("", "TestCDeclCallback")
 	if err != nil {
 		t.Fatal("TempDir failed: ", err)
 	}
@@ -602,14 +601,14 @@ uintptr_t cfunc(callback f, uintptr_t n) {
    return r;
 }
 `
-	tmpdir, err := ioutil.TempDir("", "TestReturnAfterStackGrowInCallback")
+	tmpdir, err := os.MkdirTemp("", "TestReturnAfterStackGrowInCallback")
 	if err != nil {
 		t.Fatal("TempDir failed: ", err)
 	}
 	defer os.RemoveAll(tmpdir)
 
 	srcname := "mydll.c"
-	err = ioutil.WriteFile(filepath.Join(tmpdir, srcname), []byte(src), 0)
+	err = os.WriteFile(filepath.Join(tmpdir, srcname), []byte(src), 0)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -671,14 +670,14 @@ uintptr_t cfunc(uintptr_t a, double b, float c, double d) {
 	return 0;
 }
 `
-	tmpdir, err := ioutil.TempDir("", "TestFloatArgs")
+	tmpdir, err := os.MkdirTemp("", "TestFloatArgs")
 	if err != nil {
 		t.Fatal("TempDir failed: ", err)
 	}
 	defer os.RemoveAll(tmpdir)
 
 	srcname := "mydll.c"
-	err = ioutil.WriteFile(filepath.Join(tmpdir, srcname), []byte(src), 0)
+	err = os.WriteFile(filepath.Join(tmpdir, srcname), []byte(src), 0)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -733,14 +732,14 @@ double cfuncDouble(uintptr_t a, double b, float c, double d) {
 	return 0;
 }
 `
-	tmpdir, err := ioutil.TempDir("", "TestFloatReturn")
+	tmpdir, err := os.MkdirTemp("", "TestFloatReturn")
 	if err != nil {
 		t.Fatal("TempDir failed: ", err)
 	}
 	defer os.RemoveAll(tmpdir)
 
 	srcname := "mydll.c"
-	err = ioutil.WriteFile(filepath.Join(tmpdir, srcname), []byte(src), 0)
+	err = os.WriteFile(filepath.Join(tmpdir, srcname), []byte(src), 0)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -948,7 +947,7 @@ func TestDLLPreloadMitigation(t *testing.T) {
 		t.Skip("skipping test: gcc is missing")
 	}
 
-	tmpdir, err := ioutil.TempDir("", "TestDLLPreloadMitigation")
+	tmpdir, err := os.MkdirTemp("", "TestDLLPreloadMitigation")
 	if err != nil {
 		t.Fatal("TempDir failed: ", err)
 	}
@@ -975,7 +974,7 @@ uintptr_t cfunc(void) {
 }
 `
 	srcname := "nojack.c"
-	err = ioutil.WriteFile(filepath.Join(tmpdir, srcname), []byte(src), 0)
+	err = os.WriteFile(filepath.Join(tmpdir, srcname), []byte(src), 0)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -1035,7 +1034,7 @@ func TestBigStackCallbackSyscall(t *testing.T) {
 		t.Fatal("Abs failed: ", err)
 	}
 
-	tmpdir, err := ioutil.TempDir("", "TestBigStackCallback")
+	tmpdir, err := os.MkdirTemp("", "TestBigStackCallback")
 	if err != nil {
 		t.Fatal("TempDir failed: ", err)
 	}
@@ -1184,14 +1183,14 @@ func BenchmarkOsYield(b *testing.B) {
 }
 
 func BenchmarkRunningGoProgram(b *testing.B) {
-	tmpdir, err := ioutil.TempDir("", "BenchmarkRunningGoProgram")
+	tmpdir, err := os.MkdirTemp("", "BenchmarkRunningGoProgram")
 	if err != nil {
 		b.Fatal(err)
 	}
 	defer os.RemoveAll(tmpdir)
 
 	src := filepath.Join(tmpdir, "main.go")
-	err = ioutil.WriteFile(src, []byte(benchmarkRunningGoProgram), 0666)
+	err = os.WriteFile(src, []byte(benchmarkRunningGoProgram), 0666)
 	if err != nil {
 		b.Fatal(err)
 	}
diff --git a/src/runtime/testdata/testprog/memprof.go b/src/runtime/testdata/testprog/memprof.go
index 7b134bc078..0392e60f84 100644
--- a/src/runtime/testdata/testprog/memprof.go
+++ b/src/runtime/testdata/testprog/memprof.go
@@ -7,7 +7,6 @@ package main
 import (
 	"bytes"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"runtime"
 	"runtime/pprof"
@@ -31,7 +30,7 @@ func MemProf() {
 
 	runtime.GC()
 
-	f, err := ioutil.TempFile("", "memprof")
+	f, err := os.CreateTemp("", "memprof")
 	if err != nil {
 		fmt.Fprintln(os.Stderr, err)
 		os.Exit(2)
diff --git a/src/runtime/testdata/testprog/syscalls_linux.go b/src/runtime/testdata/testprog/syscalls_linux.go
index b8ac087626..48f8014237 100644
--- a/src/runtime/testdata/testprog/syscalls_linux.go
+++ b/src/runtime/testdata/testprog/syscalls_linux.go
@@ -7,7 +7,6 @@ package main
 import (
 	"bytes"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"syscall"
 )
@@ -17,7 +16,7 @@ func gettid() int {
 }
 
 func tidExists(tid int) (exists, supported bool) {
-	stat, err := ioutil.ReadFile(fmt.Sprintf("/proc/self/task/%d/stat", tid))
+	stat, err := os.ReadFile(fmt.Sprintf("/proc/self/task/%d/stat", tid))
 	if os.IsNotExist(err) {
 		return false, true
 	}
diff --git a/src/runtime/testdata/testprog/timeprof.go b/src/runtime/testdata/testprog/timeprof.go
index 0702885369..1e90af4033 100644
--- a/src/runtime/testdata/testprog/timeprof.go
+++ b/src/runtime/testdata/testprog/timeprof.go
@@ -6,7 +6,6 @@ package main
 
 import (
 	"fmt"
-	"io/ioutil"
 	"os"
 	"runtime/pprof"
 	"time"
@@ -17,7 +16,7 @@ func init() {
 }
 
 func TimeProf() {
-	f, err := ioutil.TempFile("", "timeprof")
+	f, err := os.CreateTemp("", "timeprof")
 	if err != nil {
 		fmt.Fprintln(os.Stderr, err)
 		os.Exit(2)
diff --git a/src/runtime/testdata/testprog/vdso.go b/src/runtime/testdata/testprog/vdso.go
index ef92f48758..d2a300d8f2 100644
--- a/src/runtime/testdata/testprog/vdso.go
+++ b/src/runtime/testdata/testprog/vdso.go
@@ -8,7 +8,6 @@ package main
 
 import (
 	"fmt"
-	"io/ioutil"
 	"os"
 	"runtime/pprof"
 	"time"
@@ -19,7 +18,7 @@ func init() {
 }
 
 func signalInVDSO() {
-	f, err := ioutil.TempFile("", "timeprofnow")
+	f, err := os.CreateTemp("", "timeprofnow")
 	if err != nil {
 		fmt.Fprintln(os.Stderr, err)
 		os.Exit(2)
diff --git a/src/runtime/testdata/testprogcgo/pprof.go b/src/runtime/testdata/testprogcgo/pprof.go
index 00f2c42e93..3b73fa0bdd 100644
--- a/src/runtime/testdata/testprogcgo/pprof.go
+++ b/src/runtime/testdata/testprogcgo/pprof.go
@@ -60,7 +60,6 @@ import "C"
 
 import (
 	"fmt"
-	"io/ioutil"
 	"os"
 	"runtime"
 	"runtime/pprof"
@@ -75,7 +74,7 @@ func init() {
 func CgoPprof() {
 	runtime.SetCgoTraceback(0, unsafe.Pointer(C.pprofCgoTraceback), nil, nil)
 
-	f, err := ioutil.TempFile("", "prof")
+	f, err := os.CreateTemp("", "prof")
 	if err != nil {
 		fmt.Fprintln(os.Stderr, err)
 		os.Exit(2)
diff --git a/src/runtime/testdata/testprogcgo/threadpprof.go b/src/runtime/testdata/testprogcgo/threadpprof.go
index 37a2a1ab65..feb774ba59 100644
--- a/src/runtime/testdata/testprogcgo/threadpprof.go
+++ b/src/runtime/testdata/testprogcgo/threadpprof.go
@@ -74,7 +74,6 @@ import "C"
 
 import (
 	"fmt"
-	"io/ioutil"
 	"os"
 	"runtime"
 	"runtime/pprof"
@@ -97,7 +96,7 @@ func CgoPprofThreadNoTraceback() {
 }
 
 func pprofThread() {
-	f, err := ioutil.TempFile("", "prof")
+	f, err := os.CreateTemp("", "prof")
 	if err != nil {
 		fmt.Fprintln(os.Stderr, err)
 		os.Exit(2)
diff --git a/src/runtime/trace/trace_test.go b/src/runtime/trace/trace_test.go
index 235845df4e..b316eafe4c 100644
--- a/src/runtime/trace/trace_test.go
+++ b/src/runtime/trace/trace_test.go
@@ -10,7 +10,6 @@ import (
 	"internal/race"
 	"internal/trace"
 	"io"
-	"io/ioutil"
 	"net"
 	"os"
 	"runtime"
@@ -586,7 +585,7 @@ func saveTrace(t *testing.T, buf *bytes.Buffer, name string) {
 	if !*saveTraces {
 		return
 	}
-	if err := ioutil.WriteFile(name+".trace", buf.Bytes(), 0600); err != nil {
+	if err := os.WriteFile(name+".trace", buf.Bytes(), 0600); err != nil {
 		t.Errorf("failed to write trace file: %s", err)
 	}
 }
diff --git a/src/runtime/wincallback.go b/src/runtime/wincallback.go
index c022916422..fb452222da 100644
--- a/src/runtime/wincallback.go
+++ b/src/runtime/wincallback.go
@@ -11,7 +11,6 @@ package main
 import (
 	"bytes"
 	"fmt"
-	"io/ioutil"
 	"os"
 )
 
@@ -38,7 +37,7 @@ TEXT runtime·callbackasm(SB),7,$0
 	}
 
 	filename := fmt.Sprintf("zcallback_windows.s")
-	err := ioutil.WriteFile(filename, buf.Bytes(), 0666)
+	err := os.WriteFile(filename, buf.Bytes(), 0666)
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "wincallback: %s\n", err)
 		os.Exit(2)
@@ -66,7 +65,7 @@ TEXT runtime·callbackasm(SB),NOSPLIT|NOFRAME,$0
 		buf.WriteString("\tB\truntime·callbackasm1(SB)\n")
 	}
 
-	err := ioutil.WriteFile("zcallback_windows_arm.s", buf.Bytes(), 0666)
+	err := os.WriteFile("zcallback_windows_arm.s", buf.Bytes(), 0666)
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "wincallback: %s\n", err)
 		os.Exit(2)
@@ -82,7 +81,7 @@ package runtime
 
 const cb_max = %d // maximum number of windows callbacks allowed
 `, maxCallback))
-	err := ioutil.WriteFile("zcallback_windows.go", buf.Bytes(), 0666)
+	err := os.WriteFile("zcallback_windows.go", buf.Bytes(), 0666)
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "wincallback: %s\n", err)
 		os.Exit(2)