moby/vendor/src/code.google.com/p/go.net/ipv4/genericopt_posix.go

// Copyright 2012 The Go Authors.  All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// +build darwin freebsd linux netbsd openbsd windows

package ipv4

import (
	"syscall"
)

// TOS returns the type-of-service field value for outgoing packets.
func (c *genericOpt) TOS() (int, error) {
	if !c.ok() {
		return 0, syscall.EINVAL
	}
	fd, err := c.sysfd()
	if err != nil {
		return 0, err
	}
	return ipv4TOS(fd)
}

// SetTOS sets the type-of-service field value for future outgoing
// packets.
func (c *genericOpt) SetTOS(tos int) error {
	if !c.ok() {
		return syscall.EINVAL
	}
	fd, err := c.sysfd()
	if err != nil {
		return err
	}
	return setIPv4TOS(fd, tos)
}

// TTL returns the time-to-live field value for outgoing packets.
func (c *genericOpt) TTL() (int, error) {
	if !c.ok() {
		return 0, syscall.EINVAL
	}
	fd, err := c.sysfd()
	if err != nil {
		return 0, err
	}
	return ipv4TTL(fd)
}

// SetTTL sets the time-to-live field value for future outgoing
// packets.
func (c *genericOpt) SetTTL(ttl int) error {
	if !c.ok() {
		return syscall.EINVAL
	}
	fd, err := c.sysfd()
	if err != nil {
		return err
	}
	return setIPv4TTL(fd, ttl)
}