Annotated Swift Server

SwiftServer-Setup.swift

// 1. Create a socket reference

let sock = socket(AF_INET, SOCK_STREAM, 0) // or use AF_INET6 for IPv6
guard sock >= 0 else {
    fatalError("Failed to open socket")
}

// 2. Set socket options
// (SO_REUSEADDR allows reusing the port if server was shutdown while port active)

var reuse: Int32 = 1
let length = socklen_t(MemoryLayout<Int32>.size)
setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &reuse, length)

// 3: Bind the socket to an IP address and port number

var address = sockaddr_in()
let size = socklen_t(MemoryLayout<sockaddr_in>.size)

let portNumber = 8080
address.sin_family = sa_family_t(AF_INET) // or use AF_INET6 for IPv6
address.sin_port = in_port_t(portNumber).bigEndian
address.sin_addr.s_addr = INADDR_ANY // bind to any interface (makes your socket available publicly)

guard bind(sock, &address, size) >= 0 else {
    fatalError("Failed to bind")
}

// 4: Listen on the socket

guard listen(sock, SOMAXCONN) >= 0 else {
    fatalError("Listen failed")
}