Hang when calling lws_service(250);

[nethomas1968]

Hang in lws_service( context, / timeout_ms = / 250 );

After a few loops I see that it hangs in that call in main() in the client.c example.

[wilbur-se]

timeout_ms just two value available <0 or >=0 in new libwebsocket version. if >=0, just stop that if no event ocurr

[sajidali1996]

I am trying to receive the data from a websocket client and send back some data. I was successful with the former but got "Segmentation fault" error with the later especially adding this line got me stuck lws_write(wsi, "thank you", strlen("thank you"), LWS_WRITE_TEXT);

Following is the complete code

include

include

include

static int callback_websockets(struct lws wsi, enum lws_callback_reasons reason, void user, void in, size_t len) { switch (reason) { case LWS_CALLBACK_RECEIVE: printf("Received message from client: %.s\n", (int)len, (char *)in);

    // Send "thank you" as a response
    lws_write(wsi, "thank you", strlen("thank you"), LWS_WRITE_TEXT);
    break;

case LWS_CALLBACK_ESTABLISHED:
    printf("Client connected\n");
    // Perform actions when a client establishes a connection
    break;

case LWS_CALLBACK_CLOSED:
    printf("Client disconnected\n");
    // Perform actions when a client disconnects
    break;

default:
    // Handle other callback reasons if necessary
    break;
}

return 0;

}

static struct lws_protocols protocols[] = { {"websockets", callback_websockets, 0, 0}, {NULL, NULL, 0, 0}};

int main(int argc, char *argv[]) { struct lws_context_creation_info info; memset(&info, 0, sizeof(info));

info.port = 3000;
info.protocols = protocols;
info.gid = -1;
info.uid = -1;

struct lws_context *context = lws_create_context(&info);

if (!context)
{
    fprintf(stderr, "Error creating libwebsockets context\n");
    return -1;
}

printf("WebSocket server started on port %d...\n", info.port);

while (1)
{
    lws_service(context, 50);
    // Add other background tasks or conditions for breaking out of the loop
}

lws_context_destroy(context);

return 0;

};

[iamscottmoyers]

timeout_ms just two value available <0 or >=0 in new libwebsocket version. if >=0, just stop that if no event ocurr

I noticed this after merging in someone's recent update to this code. This example is not in a working state since the API change. I wrote this code 8 years ago after looking at the API for a few days and haven't used it since. The polling loop relied on the timeout, and clearly that wasn't their intention as at some point they deprecated it.