setsockopt()

PROTOTYPE

#include <sockets.h>

int setsockopt(int socket, int level, int optname, void *optval, int optlen);

DESCRIPTION

setsockopt() sets various options that control socket or protocol behavior. socket is a handle returned by socket(). level indicates the software layer controlled by the option. optname specifies the selected option. optval and optlen point to a parameter value and a parameter size, respectively, that are read by setsockopt(). The Supported options are listed here.

If successful, setsockopt() returns 0. Otherwise, it sets errno and returns -1.

ERROR CODES

EFAULT	optval is NULL or optlen is not correct for the specified option.
EINVAL	optval has an invalid value.
ENETDOWN	TargetTCP has not been initialized.
ENOPROTOOPT	The combination of level and optname is unsupported.
ENOTCONN	The socket is not connected and the SO_KEEPALIVE option was requested.
ENOTSOCK	socket is not a valid socket handle.
EOPNOTSUPP	Operation not supported, socket type is not correct for specified option.

EXAMPLE

  int sock, timeo;

  /*-------------------------------------------------------------------*/
  /* Reduce the receive timeout from indefinite to 10 seconds.         */
  /*-------------------------------------------------------------------*/
  timeo = 10000;
  rc = setsockopt(sock, SOL_SOCKET, SO_RCVTIMEO, &timeo, sizeof(timeo));
  if (rc < 0) goto error;