package runtime

import (
	"os"
	"syscall"
)

func getExitPipe(path string) (*os.File, error) {
	if err := syscall.Mkfifo(path, 0755); err != nil && !os.IsExist(err) {
		return nil, err
	}
	// add NONBLOCK in case the other side has already closed or else
	// this function would never return
	return os.OpenFile(path, syscall.O_RDONLY|syscall.O_NONBLOCK, 0)
}

func getControlPipe(path string) (*os.File, error) {
	if err := syscall.Mkfifo(path, 0755); err != nil && !os.IsExist(err) {
		return nil, err
	}
	return os.OpenFile(path, syscall.O_RDWR|syscall.O_NONBLOCK, 0)
}

// Signal sends the provided signal to the process
func (p *process) Signal(s os.Signal) error {
	return syscall.Kill(p.pid, s.(syscall.Signal))
}