Chapter 3. Socket Simulator - Options
SOCTEST - USER'S GUIDE
In this chapter, it describes about the options for socket.

SOL_SOCKET, IPPROTO_TCP, IPPROTO_UDP, and IPPROTO_IP options can be used.
Please refer the man page or internet public site for the details of each option.

SOL_SOCKET options

Option name	Description
SO_DEBUG	Enables recording of debugging information.
SO_ACCEPTCONN	Whether the socket is listening.
SO_REUSEADDR	Enables local address reuse.
SO_KEEPALIVE	Enables keep connections alive.
SO_DONTROUTE	Enables routing bypass for outgoing messages.
SO_BROADCAST	Enables permission to transmit broadcast messages.
SO_USELOOPBACK	Enables communication by bypassing hardware.
SO_LINGER	Linger on close if data present.
SO_OOBINLINE	Enables reception of out-of-band data in band.
SO_REUSEPORT	Enables bind the same port by multiple processes.
SO_TIMESTAMP	Enables reciept of timestamp as a control message.
SO_TIMESTAMP_MONOTONIC	Enables reciept of monotonically increasing timestamp as a control message.
SO_SNDBUF	Buffer size for output (bytes).
SO_RCVBUF	Buffer size for input (bytes).
SO_SNDLOWAT	Minimum count for output (bytes).
SO_RCVLOWAT	Minimum count for input (bytes).
SO_SNDTIMEO	Timeout value for output (seconds).
SO_RCVTIMEO	Timeout value for input (seconds).
SO_ERROR	Gets and clears error on the socket (get only).
SO_TYPE	Socket type (get only). SOCK_STREAM(1): Connection-based byte streams socket SOCK_DGRAM(2): Connectionless datagrams socket
SO_NUMRCVPKT	Number of datagrams in receive socket buffer (get only).
SO_NET_SERVICE_TYPE	Network service type. NET_SERVICE_TYPE_BE(0): Best effort NET_SERVICE_TYPE_BK(1): Background system initiated NET_SERVICE_TYPE_SIG(2): Signaling NET_SERVICE_TYPE_VI(3): Interactive Video NET_SERVICE_TYPE_VO(4): Interactive Voice NET_SERVICE_TYPE_RV(5): Responsive Multimedia Audio/Video NET_SERVICE_TYPE_AV(6): Multimedia Audio/Video Streaming NET_SERVICE_TYPE_OAM(7): Operations, Administration, and Management NET_SERVICE_TYPE_RD(8): Responsive Data
SO_NETSVC_MARKING_LEVEL	Get QoS marking in effect for socket (get only). 0: The outgoing network interface is not known 1: Default marking at layer 2 (for example Wi-Fi WMM) 2: Layer 3 DSCP marking and layer 2 marking for all Network Service Types 3: The system policy limits layer 3 DSCP marking and layer 2 marking to background Network Service Types

IPPROTO_TCP options

Option name	Description
TCP_NODELAY	Segments always sent asap (Disables Nagle algorithm).
TCP_MAXSEG	Maximum segment size (bytes) for outgoing TCP packets.
TCP_NOOPT	Disables TCP option.
TCP_NOPUSH	Disables immediately sending data with PUSH bit.
TCP_KEEPALIVE	Idle time (seconds) before keep-alive probes are sent. Same as TCP_KEEPIDLE in Linux.
TCP_CONNECTIONTIMEOUT	Sets timeout (seconds) value for connection.
TCP_RXT_CONNDROPTIME	Time (seconds) after which TCP retransmission will be stopped.
TCP_RXT_FINDROP	Drops connection after retransmitting FIN 3 times.
TCP_KEEPINTVL	Time (seconds) between individual keep-alive probes.
TCP_KEEPCNT	Maximum number of keep-alive probes.
TCP_SENDMOREACKS	Sends a TCP acknowledgement for every data.
TCP_ENABLE_ECN	Uses explicit congestion notification (ECN).
TCP_FASTOPEN	Requests kernel to use TFO for the server socket.
TCP_CONNECTION_INFO	Gets TCP connection level statistics (get only).
TCP_NOTSENT_LOWAT	Unsent and unacknowledged data size (bytes) in send buffer.

IPPROTO_UDP options

Option name	Description
UDP_NOCKSUM	Don't checksum outbound payloads.

IPPROTO_IP options

Option name	Description
IP_OPTIONS	Gets IP options on incoming IP packets. If some option are exist, displays the contents in hex dump. Sets / clears IP options on each outgoin IP packet. Content of a option needs to be registed in Data Manager beforehand.
IP_HDRINCL	Suppresses the kernel makes IP header.
IP_TOS	Sets the type-of-service field in IP header.
IP_TTL	Sets the time-to-live (hops) field in IP header.
IP_RECVOPTS	Enables reciept of all IP options as a control message.
IP_RECVRETOPTS	Enables reciept of IP options as a control message for response.
IP_RECVDSTADDR	Enables reciept of destination IP address as a control message.
IP_RETOPTS	Enables sending / reciept of IP options (in_opts) as a control message.
IP_MULTICAST_IF	Sets the IP address of interface which multicast datagram is sent.
IP_MULTICAST_TTL	Changes the TTL for outgoing multicast datagrams (range: 0 through 255).
IP_MULTICAST_LOOP	Enables looped back by the IP layer for local delivery.
IP_ADD_MEMBERSHIP	Joins a multicast group (set only).
IP_DROP_MEMBERSHIP	Drops a multicast group membership (set only).
IP_PORTRANGE	Sets the range of local port numbers. IP_PORTRANGE_DEFAULT(0): default range, normally 1024 through 5000 IP_PORTRANGE_HIGH(1): high range, normally 49152 through 65535 IP_PORTRANGE_LOW(2): low range, normally from 1024 down to 1 in descending order (May be restricted to privileged processes on iOS kernel)
IP_RECVIF	Enables reciept of interface which datagram is receibed.
IP_STRIPHDR	Drops receive of raw IP header.
IP_RECVTTL	Enables reciept of TTL as a control message.
IP_BOUND_IF	Gets / sets bound interface.
IP_PKTINFO (IP_RECVPKTINFO)	Enables sending / reciept of pktinfo as a control message.
IP_RECVTOS	Enables reciept of TOS as a control message.
IP_DONTFRAG	Don't fragment packet.