unix: add Fstatat on Darwin

Change-Id: I3a367e9346b1469d7e577524d3306b3d21f8fc43
Reviewed-on: https://go-review.googlesource.com/100895
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

unix/syscall_darwin.go

@@ -330,6 +330,7 @@ func Uname(uname *Utsname) error {
 //sys	Flock(fd int, how int) (err error)
 //sys	Fpathconf(fd int, name int) (val int, err error)
 //sys	Fstat(fd int, stat *Stat_t) (err error) = SYS_FSTAT64
+//sys	Fstatat(fd int, path string, stat *Stat_t, flags int) (err error) = SYS_FSTATAT64
 //sys	Fstatfs(fd int, stat *Statfs_t) (err error) = SYS_FSTATFS64
 //sys	Fsync(fd int) (err error)
 //sys	Ftruncate(fd int, length int64) (err error)

unix/zsyscall_darwin_386.go

@@ -693,6 +693,21 @@ func Fstat(fd int, stat *Stat_t) (err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func Fstatat(fd int, path string, stat *Stat_t, flags int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall6(SYS_FSTATAT64, uintptr(fd), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(stat)), uintptr(flags), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func Fstatfs(fd int, stat *Statfs_t) (err error) {
 	_, _, e1 := Syscall(SYS_FSTATFS64, uintptr(fd), uintptr(unsafe.Pointer(stat)), 0)
 	if e1 != 0 {

unix/zsyscall_darwin_amd64.go

@@ -693,6 +693,21 @@ func Fstat(fd int, stat *Stat_t) (err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func Fstatat(fd int, path string, stat *Stat_t, flags int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall6(SYS_FSTATAT64, uintptr(fd), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(stat)), uintptr(flags), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func Fstatfs(fd int, stat *Statfs_t) (err error) {
 	_, _, e1 := Syscall(SYS_FSTATFS64, uintptr(fd), uintptr(unsafe.Pointer(stat)), 0)
 	if e1 != 0 {

unix/zsyscall_darwin_arm.go

@@ -693,6 +693,21 @@ func Fstat(fd int, stat *Stat_t) (err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func Fstatat(fd int, path string, stat *Stat_t, flags int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall6(SYS_FSTATAT64, uintptr(fd), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(stat)), uintptr(flags), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func Fstatfs(fd int, stat *Statfs_t) (err error) {
 	_, _, e1 := Syscall(SYS_FSTATFS64, uintptr(fd), uintptr(unsafe.Pointer(stat)), 0)
 	if e1 != 0 {

unix/zsyscall_darwin_arm64.go

@@ -693,6 +693,21 @@ func Fstat(fd int, stat *Stat_t) (err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func Fstatat(fd int, path string, stat *Stat_t, flags int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall6(SYS_FSTATAT64, uintptr(fd), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(stat)), uintptr(flags), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func Fstatfs(fd int, stat *Statfs_t) (err error) {
 	_, _, e1 := Syscall(SYS_FSTATFS64, uintptr(fd), uintptr(unsafe.Pointer(stat)), 0)
 	if e1 != 0 {