ServerSocket throws InvalidArgumentException, but docs don't specify why. Why? - c++

Question

I'm using Poco to create a webserver. I ran into an error with the ServerSocket library. Here's the minimum code to reproduce the error.
#include <iostream>
#include "Poco/Net/ServerSocket.h"
#include "Poco/Net/StreamSocket.h"
#include "Poco/Net/SocketAddress.h"
#define PORT (unsigned short) 3000
int main()
{
Poco::Net::ServerSocket x;
x.bind(PORT);
Poco::Net::StreamSocket conn;
Poco::Net::SocketAddress clientAddr;
try {
conn = x.acceptConnection(clientAddr);
}
catch (Poco::InvalidArgumentException e) {
printf("Oh no! %s\n", e.displayText().c_str());
return 1;
}
printf("Huzzah!");
return 0;
}
I tried to look at [the docs] (https://pocoproject.org/docs/Poco.Net.ServerSocket.html#25093) to understand the error, but it doesn't even list this function as throwing this error. I've also tried the parameterless version of the function, and it still throws this exception, (which indicates to me it's not the function but a sub function throwing the error). Why? and how can I fix it, or work around it?

Answer 1

As WhozCraig said, the problem was not putting it in listening state. The code should be
#include <iostream>
#include "Poco/Net/ServerSocket.h"
#include "Poco/Net/StreamSocket.h"
#include "Poco/Net/SocketAddress.h"
#define PORT (unsigned short) 3000
int main()
{
Poco::Net::ServerSocket x;
x.bind(PORT);
x.listen(1); // or number of acceptable connections
Poco::Net::StreamSocket conn;
Poco::Net::SocketAddress clientAddr;
try {
conn = x.acceptConnection(clientAddr);
}
catch (const Poco::InvalidArgumentException& e) {
printf("Oh no! %s\n", e.displayText().c_str());
return 1;
}
printf("Huzzah!");
return 0;
}