| nn_setsockopt(3) |
| ================ |
| |
| NAME |
| ---- |
| nn_setsockopt - set a socket option |
| |
| |
| SYNOPSIS |
| -------- |
| *#include <nanomsg/nn.h>* |
| |
| *int nn_setsockopt (int 's', int 'level', int 'option', const void '*optval', size_t 'optvallen');* |
| |
| |
| DESCRIPTION |
| ----------- |
| Sets the value of the 'option'. The 'level' argument specifies the protocol |
| level at which the option resides. For generic socket-level options use |
| _NN_SOL_SOCKET_ level. For socket-type-specific options use socket type |
| for 'level' argument (e.g. _NN_SUB_). For transport-specific options use ID of |
| the transport as the 'level' argument (e.g. _NN_TCP_). |
| |
| The new value is pointed to by 'optval' argument. Size of the option is |
| specified by the 'optvallen' argument. |
| |
| _<nanomsg/nn.h>_ header defines generic socket-level options |
| (_NN_SOL_SOCKET_ level). The options are as follows: |
| |
| *NN_LINGER*:: |
| Specifies how long the socket should try to send pending outbound messages |
| after _nn_close()_ have been called, in milliseconds. Negative value means |
| infinite linger. The type of the option is int. Default value |
| is 1000 (1 second). |
| *NN_SNDBUF*:: |
| Size of the send buffer, in bytes. To prevent blocking for messages larger |
| than the buffer, exactly one message may be buffered in addition to the data |
| in the send buffer. The type of this option is int. Default value is 128kB. |
| *NN_RCVBUF*:: |
| Size of the receive buffer, in bytes. To prevent blocking for messages |
| larger than the buffer, exactly one message may be buffered in addition |
| to the data in the receive buffer. The type of this option is int. Default |
| value is 128kB. |
| *NN_SNDTIMEO*:: |
| The timeout for send operation on the socket, in milliseconds. If message |
| cannot be sent within the specified timeout, EAGAIN error is returned. |
| Negative value means infinite timeout. The type of the option is int. |
| Default value is -1. |
| *NN_RCVTIMEO*:: |
| The timeout for recv operation on the socket, in milliseconds. If message |
| cannot be received within the specified timeout, EAGAIN error is returned. |
| Negative value means infinite timeout. The type of the option is int. |
| Default value is -1. |
| *NN_RECONNECT_IVL*:: |
| For connection-based transports such as TCP, this option specifies how |
| long to wait, in milliseconds, when connection is broken before trying |
| to re-establish it. Note that actual reconnect interval may be randomised |
| to some extent to prevent severe reconnection storms. The type of the option |
| is int. Default value is 100 (0.1 second). |
| *NN_RECONNECT_IVL_MAX*:: |
| This option is to be used only in addition to _NN_RECONNECT_IVL_ option. |
| It specifies maximum reconnection interval. On each reconnect attempt, |
| the previous interval is doubled until _NN_RECONNECT_IVL_MAX_ is reached. |
| Value of zero means that no exponential backoff is performed and reconnect |
| interval is based only on _NN_RECONNECT_IVL_. If _NN_RECONNECT_IVL_MAX_ is |
| less than _NN_RECONNECT_IVL_, it is ignored. The type of the option is int. |
| Default value is 0. |
| *NN_SNDPRIO*:: |
| Sets outbound priority for endpoints subsequently added to the socket. This |
| option has no effect on socket types that send messages to all the peers. |
| However, if the socket type sends each message to a single peer |
| (or a limited set of peers), peers with high priority take precedence |
| over peers with low priority. The type of the option is int. Highest |
| priority is 1, lowest priority is 16. Default value is 8. |
| *NN_RCVPRIO*:: |
| Sets inbound priority for endpoints subsequently added to the socket. This |
| option has no effect on socket types that are not able to receive messages. |
| When receiving a message, messages from peer with higher priority are |
| received before messages from peer with lower priority. The type of the |
| option is int. Highest priority is 1, lowest priority is 16. Default value |
| is 8. |
| *NN_IPV4ONLY*:: |
| If set to 1, only IPv4 addresses are used. If set to 0, both IPv4 and IPv6 |
| addresses are used. The type of the option is int. Default value is 1. |
| *NN_SOCKET_NAME*:: |
| Socket name for error reporting and statistics. The type of the option |
| is string. Default value is "socket.N" where N is socket integer. |
| *This option is experimental, see linknanomsg:nn_env[7] for details* |
| |
| |
| RETURN VALUE |
| ------------ |
| If the function succeeds zero is returned. Otherwise, -1 is |
| returned and 'errno' is set to to one of the values defined below. |
| |
| |
| ERRORS |
| ------ |
| *EBADF*:: |
| The provided socket is invalid. |
| *ENOPROTOOPT*:: |
| The option is unknown at the level indicated. |
| *EINVAL*:: |
| The specified option value is invalid. |
| *ETERM*:: |
| The library is terminating. |
| |
| EXAMPLE |
| ------- |
| |
| ---- |
| int linger = 1000; |
| nn_setsockopt (s, NN_SOL_SOCKET, NN_LINGER, &linger, sizeof (linger)); |
| nn_setsockopt (s, NN_SUB, NN_SUB_SUBSCRIBE, "ABC", 3); |
| ---- |
| |
| |
| SEE ALSO |
| -------- |
| linknanomsg:nn_socket[3] |
| linknanomsg:nn_getsockopt[3] |
| linknanomsg:nanomsg[7] |
| |
| AUTHORS |
| ------- |
| Martin Sustrik <sustrik@250bpm.com> |
| |
