zephyr-net-socket

Zephyr Network Sockets

Quick Start

1. Enable Sockets: CONFIG_NET_SOCKETS=y in prj.conf
2. Choose Protocol: TCP (CONFIG_NET_TCP=y) or UDP (CONFIG_NET_UDP=y)
3. Optional TLS: CONFIG_NET_SOCKETS_SOCKOPT_TLS=y for secure sockets
4. Optional DNS: CONFIG_DNS_RESOLVER=y for hostname resolution
5. Create Socket: socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)

Core TCP Client Pattern

#include <zephyr/net/socket.h>

int tcp_client_example(void)
{
    struct sockaddr_in addr = {
        .sin_family = AF_INET,
        .sin_port = htons(8080),
    };
    inet_pton(AF_INET, "192.168.1.100", &addr.sin_addr);

    int sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
    if (sock < 0) {
        return -errno;
    }

    int ret = connect(sock, (struct sockaddr *)&addr, sizeof(addr));
    if (ret < 0) {
        close(sock);
        return -errno;
    }

    /* Send/receive data */
    send(sock, "Hello", 5, 0);

    char buf[128];
    int len = recv(sock, buf, sizeof(buf), 0);

    close(sock);
    return 0;
}

Core TCP Server Pattern

int tcp_server_example(void)
{
    struct sockaddr_in addr = {
        .sin_family = AF_INET,
        .sin_port = htons(8080),
        .sin_addr.s_addr = INADDR_ANY,
    };

    int sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
    if (sock < 0) {
        return -errno;
    }

    int ret = bind(sock, (struct sockaddr *)&addr, sizeof(addr));
    if (ret < 0) {
        close(sock);
        return -errno;
    }

    ret = listen(sock, 5);  /* Backlog of 5 */
    if (ret < 0) {
        close(sock);
        return -errno;
    }

    while (1) {
        struct sockaddr_in client_addr;
        socklen_t client_len = sizeof(client_addr);
        int client = accept(sock, (struct sockaddr *)&client_addr, &client_len);
        if (client < 0) {
            continue;
        }

        /* Handle client connection */
        char buf[128];
        int len = recv(client, buf, sizeof(buf), 0);
        if (len > 0) {
            send(client, buf, len, 0);  /* Echo back */
        }

        close(client);
    }
}