| nn_socket(3) |
| ============ |
| |
| NAME |
| ---- |
| nn_socket - create an SP socket |
| |
| |
| SYNOPSIS |
| -------- |
| *#include <nanomsg/nn.h>* |
| |
| *int nn_socket (int 'domain', int 'protocol');* |
| |
| |
| DESCRIPTION |
| ----------- |
| Creates an SP socket with specified 'domain' and 'protocol'. Returns a file |
| descriptor for the newly created socket. |
| |
| Following domains are defined at the moment: |
| |
| *AF_SP*:: |
| Standard full-blown SP socket. |
| |
| *AF_SP_RAW*:: |
| Raw SP socket. Raw sockets omit the end-to-end functionality found in AF_SP |
| sockets and thus can be used to implement intermediary devices in SP topologies. |
| |
| 'protocol' parameter defines the type of the socket, which in turn determines |
| the exact semantics of the socket. Check manual pages for individual SP |
| protocols to get the list of available socket types. |
| |
| The newly created socket is initially not associated with any endpoints. |
| In order to establish a message flow at least one endpoint has to be added |
| to the socket using linknanomsg:nn_bind[3] or linknanomsg:nn_connect[3] |
| function. |
| |
| Also note that 'type' argument as found in standard _socket(2)_ function is |
| omitted from _nn_socket_. All the SP sockets are message-based and thus of |
| _SOCK_SEQPACKET_ type. |
| |
| |
| RETURN VALUE |
| ------------ |
| If the function succeeds file descriptor of the new socket is returned. |
| Otherwise, -1 is returned and 'errno' is set to to one of |
| the values defined below. |
| |
| Note that file descriptors returned by _nn_socket_ function are not standard |
| file descriptors and will exhibit undefined behaviour when used with system |
| functions. Moreover, it may happen that a system file descriptor and file |
| descriptor of an SP socket will incidentally collide (be equal). |
| |
| |
| ERRORS |
| ------ |
| *EAFNOSUPPORT*:: |
| Specified address family is not supported. |
| *EINVAL*:: |
| Unknown protocol. |
| *EMFILE*:: |
| The limit on the total number of open SP sockets or OS limit for file |
| descriptors has been reached. |
| *ETERM*:: |
| The library is terminating. |
| |
| EXAMPLE |
| ------- |
| |
| ---- |
| int s = nn_socket (AF_SP, NN_PUB); |
| assert (s >= 0); |
| ---- |
| |
| |
| SEE ALSO |
| -------- |
| linknanomsg:nn_pubsub[7] |
| linknanomsg:nn_reqrep[7] |
| linknanomsg:nn_pipeline[7] |
| linknanomsg:nn_survey[7] |
| linknanomsg:nn_bus[7] |
| linknanomsg:nn_bind[3] |
| linknanomsg:nn_connect[3] |
| linknanomsg:nn_close[3] |
| linknanomsg:nanomsg[7] |
| |
| AUTHORS |
| ------- |
| Martin Sustrik <sustrik@250bpm.com> |
| |
