Replace deprecated io/ioutil usage

Author: tklauser

go.mod

@@ -1,5 +1,5 @@
 module github.com/tklauser/ps
 
-go 1.13
+go 1.16
 
 require golang.org/x/sys v0.11.0

process_procfs_stat.go

@@ -10,7 +10,7 @@ package ps
 import (
 	"bytes"
 	"fmt"
-	"io/ioutil"
+	"os"
 	"path/filepath"
 	"strconv"
 	"strings"
@@ -28,7 +28,7 @@ func newUnixProcess(pid int) (Process, error) {
 	} else if err != nil {
 		return nil, fmt.Errorf("failed to lstat %s: %w", procDir, err)
 	}
-	b, err := ioutil.ReadFile(filepath.Join(procDir, "stat"))
+	b, err := os.ReadFile(filepath.Join(procDir, "stat"))
 	if err != nil {
 		return nil, err
 	}
@@ -55,7 +55,7 @@ func newUnixProcess(pid int) (Process, error) {
 	p.command = string(comm)
 	p.executablePath, _ = filepath.EvalSymlinks(filepath.Join(procDir, "exe"))
 
-	b, err = ioutil.ReadFile(filepath.Join(procDir, "cmdline"))
+	b, err = os.ReadFile(filepath.Join(procDir, "cmdline"))
 	if err == nil && len(b) > 0 {
 		p.executableArgs = strings.FieldsFunc(string(b), func(r rune) bool {
 			return r == '\u0000'

process_solaris.go

@@ -7,7 +7,6 @@ package ps
 import (
 	"encoding/binary"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strconv"
@@ -115,7 +114,7 @@ func newUnixProcess(pid int) (Process, error) {
 
 	p.executablePath, _ = filepath.EvalSymlinks(filepath.Join(procDir, "path", "a.out"))
 
-	b, err := ioutil.ReadFile(filepath.Join(procDir, "cmdline"))
+	b, err := os.ReadFile(filepath.Join(procDir, "cmdline"))
 	if err == nil && len(b) > 0 {
 		p.executableArgs = strings.FieldsFunc(string(b), func(r rune) bool {
 			return r == '\u0000'

process_test.go

@@ -6,7 +6,6 @@ package ps_test
 
 import (
 	"bytes"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"runtime"
@@ -122,7 +121,7 @@ func getInitName() string {
 		return "init"
 	case "linux":
 		// might be systemd, sysv init, openrc, ...
-		b, err := ioutil.ReadFile("/proc/1/comm")
+		b, err := os.ReadFile("/proc/1/comm")
 		if err == nil {
 			return string(bytes.Trim(b, " \r\n"))
 		}