// Copyright 2017 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

// +build !windows

package differ

import "syscall"

// isatty reports whether fd is a tty.
// Actually it reports whether fd is a character device, which is close enough.
func isatty(fd int) bool {
	var st syscall.Stat_t
	if err := syscall.Fstat(fd, &st); err != nil {
		return false
	}
	return st.Mode&syscall.S_IFMT == syscall.S_IFCHR
}