SETSOCKOPT

The SETSOCKOPT call sets options associated with the specified socket.

SOCKET SETSOCKOPT,(socket,level,optname,optval,optlen)
socket
is the address of a fullword integer socket descriptor.
level
is the address of a fullword integer containing the option level. SOL_SOCK (X'FFFF') is the only supported level. It refers to the socket protocol level, as opposed to the TCP or IP levels.
optname
is the address of a fullword containing an option name.
optval
is the address of a string containing the option value. This is a fullword integer except for the SO_LINGER option, which is a doubleword.
optlen
is the address of a fullword containing the length of the optval parameter.