shutdown and recv

hoge.cpp

// g++ -std=gnu++11 hoge.cpp -lpthread

#include <cerrno>
#include <chrono>
#include <cstring>
#include <iostream>
#include <netdb.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <system_error>
#include <thread>

using namespace std;

void recv_thread(int fd) {
    char buf[100];
    while( true ) {
        ssize_t r = ::recv(fd, buf, sizeof(buf), 0);
        cerr << "recv returns " << r << endl;
        if( r == 0 )
            break;
        if( r == -1 ) {
            error_code e{errno, std::system_category()};
            cerr << "recv: " << e << endl;
            break;
        }
    }
}

int main(int argc, char** argv) {
    if( argc != 3 ) {
        cerr << "Usage: hoge HOST PORT" << endl;
        return 0;
    }

    struct addrinfo hints, *r;
    memset(&hints, 0, sizeof(hints));
    hints.ai_family = AF_INET;
    hints.ai_socktype = SOCK_STREAM;
    hints.ai_flags = 0;
    hints.ai_protocol = 0;
    int e = getaddrinfo(argv[1], argv[2], &hints, &r);
    if( e != 0 ) {
        cerr << "getaddrinfo: " << gai_strerror(e) << endl;
        return 1;
    }
    if( r == nullptr ) {
        cerr << "getaddrinfo: No result" << endl;
        return 1;
    }

    int s = ::socket(r->ai_family, r->ai_socktype, r->ai_protocol);
    e = ::connect(s, r->ai_addr, r->ai_addrlen);
    freeaddrinfo(r);
    if( e != 0 ) {
        error_code e{errno, std::system_category()};
        cerr << "connect: " << e << endl;
        return 1;
    }

    thread t1(recv_thread, s);
    cerr << "start recv thread ..." << endl;
    this_thread::sleep_for( chrono::seconds{1} );
    cerr << "shutdown socket ..." << endl;
    ::shutdown(s, SHUT_RD);
    cerr << "joining ..." << endl;
    t1.join();
    cerr << "done." << endl;
    return 0;
}