Function log_error

example/netcat_timeout.cpp:8–13

using Socket = co_context::socket;

void log_error(int err) {
    switch (err) {
        case ECANCELED: log::e("timeout\n"); break;
        default:        log::e("%s\n", strerror(err)); break;
    }
}

task<> session(Socket sock) {
    char buf[8192];