Minimal libwebsockets client to read from Binance. Compile with `gcc -obinance binance.c -lwebsockets`

binance.c

#include <stdio.h>
#include <stdbool.h>
#include <signal.h>
#include <libwebsockets.h>

static bool bExit;

static int callback(struct lws *wsi, enum lws_callback_reasons reason, void *user, void *in, size_t len);

static const struct lws_protocols protocols[] = {
	{ "lws-minimal-client", callback, 0, 0, 0, NULL, 0 },
	LWS_PROTOCOL_LIST_TERM
};

static const struct lws_extension extensions[] = {
	{
		"permessage-deflate",
		lws_extension_callback_pm_deflate,
		"permessage-deflate"
		 "; client_no_context_takeover"
		 "; client_max_window_bits"
	},
	{ NULL, NULL, NULL /* terminator */ }
};

static int callback(struct lws *wsi, enum lws_callback_reasons reason, void *user, void *in, size_t len) {
	switch (reason) {
	case LWS_CALLBACK_CLIENT_CONNECTION_ERROR:
		printf("error: %s\n", in ? (char *)in : "(null)");
		return -1;

	case LWS_CALLBACK_CLIENT_RECEIVE:
		printf("%s\n", (char *)in);
		break;

	case LWS_CALLBACK_CLIENT_ESTABLISHED:
		printf("connected\n");
		break;

	case LWS_CALLBACK_CLIENT_CLOSED:
		printf("closed\n");
		bExit = true;
		return -1;
		
	default:
		break;
	}

	return 0;
}

static void handle_sigint(int sig) {
	bExit = true;
}

int main(int argc, const char **argv) {
	struct lws_context *context;
	struct lws_client_connect_info i;
	struct lws_context_creation_info info;

	lws_set_log_level(LLL_ERR | LLL_WARN, lwsl_emit_syslog); // We don't need to see the notice messages
	signal(SIGINT, handle_sigint);

	memset(&i, 0, sizeof(i));
	memset(&info, 0, sizeof info);

	info.options = LWS_SERVER_OPTION_DO_SSL_GLOBAL_INIT;
	info.port = CONTEXT_PORT_NO_LISTEN; /* we do not run any server */
	info.protocols = protocols;
	info.fd_limit_per_thread = 1 + 1 + 1;
	info.extensions = extensions;

	context = lws_create_context(&info);
	if (!context) {
		printf("error creating context\n");
		return -1;
	}

	i.context = context;
	i.port = 9443;
	i.address = "stream.binance.com";
	i.path = "/ws/btcusdt@aggTrade";
	i.host = i.address;
	i.origin = i.address;
	i.ssl_connection = LCCSCF_USE_SSL | LCCSCF_PRIORITIZE_READS;
	i.protocol = NULL;
	i.local_protocol_name = "lws-minimal-client";

	if (!lws_client_connect_via_info(&i)) {
		printf("error connecting\n");
		return -1;
	}

	while (!bExit) {
		lws_service(context, 0);
	}

	lws_context_destroy(context);
	printf("finished\n");

	return 0;
}