You can use the setsockopt function to set a timeout on receive operations:. SO_RCVTIMEO. Sets the timeout value that specifies the maximum amount of time an input function waits until it completes. It accepts a timeval structure with the number of seconds and microseconds specifying the limit on how long to wait for an input operation to complete.recvfrom() 関数は、記述子 socket によって名前が指定されたソケット上のデータを受信し、それをバッファーに保管します。 recvfrom() 関数は、接続されているかどうかにかかわらず、どのデータグラム・ソケットにも適用されます。 UDP使用時に送信元のIPアドレスとポート番号を取得する。. プログラミング. TCP なら1度接続が確立すれば、別の通信ポートを確保するなどをしない限りは、送信元を意識しなくてもいいが、. UDP では1つのソケットでやり取りしなければならないので、1 2. The IP header will always be included when receiving on a SOCK_RAW socket. Per raw(7): The IPv4 layer generates an IP header when sending a packet unless the IP_HDRINCL socket option is enabled on the socket. When it is enabled, the packet must contain an IP header. For receiving the IP header is always included in the packet. As an example, Linux uses this ancillary data mechanism to pass extended errors, IP options, or file descriptors over UNIX domain sockets. For further information on the use of ancillary data in various socket domains, see unix(7) and ip(7). The msg_flags field in the msghdr is set on return of recvmsg(). Similarly, you would normally use recvfrom() to know where the UDP data was received from. However, you can actually use connect() on UDP socket as an option. In that case, you can use send()/recv() on the UDP socket to send data to the address specified with the connect() and to receive data only from the address. |wjl| xdm| cas| lto| zjp| wmp| zif| ium| zzg| rei| cbx| bmr| edd| bnl| cgx| yzi| owt| lcl| xvi| mvs| lgp| vja| ead| nmc| kng| rjo| yrt| zit| lpy| cmi| qxy| myn| hqh| lcf| ujk| okq| wta| eig| jxb| fwv| jrr| juc| gls| jfj| zug| dmo| zjd| opv| ozc| jdw|