tcpdialer.go
func (d *TCPDialer) Dial(addr string) (net.Conn, error) {
	return d.dial(addr, false, DefaultDialTimeout)
}
func (d *TCPDialer) Dial(addr string) (net.Conn, error) {
	return d.dial(addr, false, DefaultDialTimeout)
}
func ( d * TCPDialer ) Dial ( addr string ) ( net . Conn , error ) { return d . dial ( addr , false , DefaultDialTimeout ) }
// Dial dials the given TCP addr using tcp4.
//
// This function has the following additional features comparing to net.Dial:
//
//   * It reduces load on DNS resolver by caching resolved TCP addressed
//     for DefaultDNSCacheDuration.
//   * It dials all the resolved TCP addresses in round-robin manner until
//     connection is established. This may be useful if certain addresses
//     are temporarily unreachable.
//   * It returns ErrDialTimeout if connection cannot be established during
//     DefaultDialTimeout seconds. Use DialTimeout for customizing dial timeout.
//
// This dialer is intended for custom code wrapping before passing
// to Client.Dial or HostClient.Dial.
//
// For instance, per-host counters and/or limits may be implemented
// by such wrappers.
//
// The addr passed to the function must contain port. Example addr values:
//
//     * foobar.baz:443
//     * foo.bar:80
//     * aaa.com:8080
Dial dials the given TCP addr using tcp4 . This function has the following additional features comparing to net . Dial : * It reduces load on DNS resolver by caching resolved TCP addressed for DefaultDNSCacheDuration . * It dials all the resolved TCP addresses in round - robin manner until connection is established . This may be useful if certain addresses are temporarily unreachable . * It returns ErrDialTimeout if connection cannot be established during DefaultDialTimeout seconds . Use DialTimeout for customizing dial timeout . This dialer is intended for custom code wrapping before passing to Client . Dial or HostClient . Dial . For instance per - host counters and / or limits may be implemented by such wrappers . The addr passed to the function must contain port . Example addr values : * foobar . baz : 443 * foo . bar : 80 * aaa . com : 8080