diff --git a/cmd/zenity/main.go b/cmd/zenity/main.go
index fa6feaf..a2563c2 100644
--- a/cmd/zenity/main.go
+++ b/cmd/zenity/main.go
@@ -52,6 +52,7 @@ var (
 	icon          string
 	windowIcon    string
 	attach        string
+	modal         bool
 	multiple      bool
 	defaultCancel bool
 
@@ -211,7 +212,7 @@ func setupFlags() {
 	flag.StringVar(&text, "text", "", "Set the dialog `text`")
 	flag.StringVar(&windowIcon, "window-icon", "", "Set the window `icon` (error, info, question, warning)")
 	flag.StringVar(&attach, "attach", "", "Set the parent `window` to attach to")
-	flag.Bool("modal", true, "Set the modal hint")
+	flag.BoolVar(&modal, "modal", runtime.GOOS == "darwin", "Set the modal hint")
 	flag.BoolVar(&multiple, "multiple", false, "Allow multiple items to be selected")
 	flag.BoolVar(&defaultCancel, "default-cancel", false, "Give Cancel button focus by default")
 
@@ -448,6 +449,10 @@ func loadFlags() []zenity.Option {
 
 	if attach != "" {
 		opts = append(opts, zenity.Attach(zenutil.ParseWindowId(attach)))
+	} else if modal {
+		if pid := zenutil.GetParentWindowId(); pid != 0 {
+			opts = append(opts, zenity.Attach(pid))
+		}
 	}
 
 	// Message options
diff --git a/go.mod b/go.mod
index 357a5e5..158374e 100644
--- a/go.mod
+++ b/go.mod
@@ -9,7 +9,7 @@ require (
 	github.com/randall77/makefat v0.0.0-20210315173500-7ddd0e42c844
 	go.uber.org/goleak v1.1.12 // test
 	golang.org/x/image v0.0.0-20220601225756-64ec528b34cd
-	golang.org/x/sys v0.0.0-20220520151302-bc2c85ada10a
+	golang.org/x/sys v0.0.0-20220610221304-9f5ed59c137d
 )
 
 require (
diff --git a/go.sum b/go.sum
index 1a948ca..a4e7300 100644
--- a/go.sum
+++ b/go.sum
@@ -42,8 +42,8 @@ golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210330210617-4fbd30eecc44/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210510120138-977fb7262007/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.0.0-20220520151302-bc2c85ada10a h1:dGzPydgVsqGcTRVwiLJ1jVbufYwmzD3LfVPLKsKg+0k=
-golang.org/x/sys v0.0.0-20220520151302-bc2c85ada10a/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20220610221304-9f5ed59c137d h1:Zu/JngovGLVi6t2J3nmAf3AoTDwuzw85YZ3b9o4yU7s=
+golang.org/x/sys v0.0.0-20220610221304-9f5ed59c137d/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
diff --git a/internal/zenutil/window_darwin.go b/internal/zenutil/window_darwin.go
index 3bffc43..51c74df 100644
--- a/internal/zenutil/window_darwin.go
+++ b/internal/zenutil/window_darwin.go
@@ -3,8 +3,8 @@ package zenutil
 import (
 	"os"
 	"strconv"
-	"syscall"
-	"unsafe"
+
+	"golang.org/x/sys/unix"
 )
 
 // ParseWindowId is internal.
@@ -17,75 +17,20 @@ func ParseWindowId(id string) any {
 
 // GetParentWindowId is internal.
 func GetParentWindowId() int {
-	buf, err := sysctlKernProcAll()
-	if err != nil {
-		return 0
-	}
-
-	type kinfo_proc struct {
-		_    [40]byte
-		Pid  int32
-		_    [516]byte
-		PPid int32
-		_    [84]byte
-	}
-	const size = int(unsafe.Sizeof(kinfo_proc{}))
-
-	ppids := map[int]int{}
-	for i := 0; i+size < len(buf); i += size {
-		p := (*kinfo_proc)(unsafe.Pointer(&buf[i]))
-		ppids[int(p.Pid)] = int(p.PPid)
-	}
-
 	pid := os.Getppid()
 	for {
-		ppid := ppids[pid]
+		kinfo, err := unix.SysctlKinfoProc("kern.proc.pid", pid)
+		if err != nil {
+			return 0
+		}
+		ppid := kinfo.Eproc.Ppid
 		switch ppid {
 		case 0:
 			return 0
 		case 1:
 			return pid
 		default:
-			pid = ppid
+			pid = int(ppid)
 		}
 	}
 }
-
-func sysctlKernProcAll() ([]byte, error) {
-	const (
-		CTRL_KERN     = 1
-		KERN_PROC     = 14
-		KERN_PROC_ALL = 0
-	)
-
-	mib := [4]int32{CTRL_KERN, KERN_PROC, KERN_PROC_ALL, 0}
-	size := uintptr(0)
-
-	_, _, errno := syscall.Syscall6(
-		syscall.SYS___SYSCTL,
-		uintptr(unsafe.Pointer(&mib[0])),
-		uintptr(len(mib)),
-		0,
-		uintptr(unsafe.Pointer(&size)),
-		0,
-		0)
-
-	if errno != 0 {
-		return nil, errno
-	}
-
-	bs := make([]byte, size)
-	_, _, errno = syscall.Syscall6(
-		syscall.SYS___SYSCTL,
-		uintptr(unsafe.Pointer(&mib[0])),
-		uintptr(len(mib)),
-		uintptr(unsafe.Pointer(&bs[0])),
-		uintptr(unsafe.Pointer(&size)),
-		0,
-		0)
-
-	if errno != 0 {
-		return nil, errno
-	}
-	return bs[0:size], nil
-}