Use send/sendmsg and don't ignore SIGPIPE

src/connection.cpp

@@ -134,7 +134,11 @@ bool Connection::writeBytes() {
 
     ssize_t w;
     for (;;) {
-      w = writev(fd_, iov, iov_count);
+      struct msghdr msg = {};
+      msg.msg_iov = iov;
+      msg.msg_iovlen = iov_count;
+
+      w = sendmsg(fd_, &msg, MSG_NOSIGNAL);
       if (w == -1) {
         if (errno == EINTR) {
           continue; // Standard practice: retry on signal interruption
@@ -148,7 +152,7 @@ bool Connection::writeBytes() {
           }
           return false;
         }
-        perror("writev");
+        perror("sendmsg");
         return true;
       }
       break;