:mod:`socket` --- Internet communication
.. module:: socket :synopsis: Internet communication.
Sockets are used to communicate over IP networks. TCP and UDP are the most common transport protocols.
No more than one thread may read from a socket at any given moment. The same applies when writing to a socket. The reader and writer may be different threads, though. The behaviour is undefined if more threads use the same socket simultaneously. The application will likely crash. Add a semaphore to protect the socket if more threads need access to a socket.
Below is a TCP client example that connects to a server and sends data.
uint8_t buf[16];
struct socket_t tcp;
struct inet_addr_t local_addr, remote_addr;
/* Set the local and remote addresses. */
inet_aton("192.168.1.103", &local_addr.ip);
local_addr.port = 6000;
inet_aton("192.168.1.106", &remote_addr.ip);
remote_addr.port = 5000;
/* Initialize the socket and connect to the server. */
socket_open_tcp(&tcp);
socket_bind(&tcp, &local_addr);
socket_connect(&tcp, &remote_addr);
/* Send the data. */
memset(buf, 0, sizeof(buf));
socket_write(&tcp, buf, sizeof(buf));
/* Close the connection. */
socket_close(&tcp);And below is the same scenario for UDP.
uint8_t buf[16];
struct socket_t udp;
struct socket_addr_t local_addr, remote_addr;
/* Set the local and remote addresses. */
inet_aton("192.168.1.103", &local_addr.ip);
local_addr.port = 6000;
inet_aton("192.168.1.106", &remote_addr.ip);
remote_addr.port = 5000;
/* Initialize the socket and connect to the server. */
socket_open_udp(&udp);
socket_bind(&udp, &local_addr);
socket_connect(&udp, &remote_addr);
/* Send the data. */
memset(buf, 0, sizeof(buf));
socket_send(&udp, buf, sizeof(buf));
/* Close the connection. */
socket_close(&udp);Source code: :github-blob:`src/inet/socket.h`, :github-blob:`src/inet/socket.c`
.. doxygenfile:: inet/socket.h :project: simba