// +build darwin freebsd openbsd netbsd
// +build !appengine

package isatty

import (
	"syscall"
	"unsafe"
)

const ioctlReadTermios = syscall.TIOCGETA

// IsTerminal return true if the file descriptor is terminal.
func IsTerminal(fd uintptr) bool {
	var termios syscall.Termios
	_, _, err := syscall.Syscall6(syscall.SYS_IOCTL, fd, ioctlReadTermios, uintptr(unsafe.Pointer(&termios)), 0, 0, 0)
	return err == 0
}

// +build darwin freebsd openbsd netbsd dragonfly
// +build !appengine

package isatty

import (
	"syscall"
	"unsafe"
)

const ioctlReadTermios = syscall.TIOCGETA

// IsTerminal return true if the file descriptor is terminal.
func IsTerminal(fd uintptr) bool {
	var termios syscall.Termios
	_, _, err := syscall.Syscall6(syscall.SYS_IOCTL, fd, ioctlReadTermios, uintptr(unsafe.Pointer(&termios)), 0, 0, 0)
	return err == 0
}

Add dragonfly to bsd build
Add dragonfly to bsd build

Dragonfly is a BSD, too.