The new type [KeepAliveConfig] permits fine-tuning the keep-alive
options for TCP connections, via a new [TCPConn.SetKeepAliveConfig]

pkg net/http, method (*ProtocolError) Is(error) bool #41198
pkg net/http, method (*ResponseController) EnableFullDuplex() error #57786
pkg net/http, var ErrSchemeMismatch error #44855
pkg net, method (*Dialer) MultipathTCP() bool #56539
pkg net, method (*Dialer) SetMultipathTCP(bool) #56539
pkg net, method (*ListenConfig) MultipathTCP() bool #56539
pkg net, method (*ListenConfig) SetMultipathTCP(bool) #56539

pkg net, method (*TCPConn) SetKeepAliveConfig(KeepAliveConfig) error #62254
pkg net, type Dialer struct, KeepAliveConfig KeepAliveConfig #62254
pkg net, type KeepAliveConfig struct #62254
pkg net, type KeepAliveConfig struct, Count int #62254
pkg net, type KeepAliveConfig struct, Enable bool #62254
pkg net, type KeepAliveConfig struct, Idle time.Duration #62254
pkg net, type KeepAliveConfig struct, Interval time.Duration #62254

Go 1.21 adds the support of Multipath TCP but it is only used if the application
explicitly asked for it. This behavior can be controlled by the
[`multipathtcp` setting](/pkg/net#Dialer.SetMultipathTCP).

There is no plan to remove any of these settings.

### Go 1.20

Go 1.20 introduced support for rejecting insecure paths in tar and zip archives,

// deliver a final empty token (which is different from a nil token).
// One could achieve the same behavior with a custom error value but
// providing one here is tidier.
// See the emptyFinalToken example for a use of this value.
var ErrFinalToken = errors.New("final token")

// Scan advances the [Scanner] to the next token, which will then be