Destroy agent on disconnect; another agent can connect later

connection.cc

@@ -12,5 +12,6 @@ connection::senses(int tick_id, char around[4])
 {
 	char buf[1024];
 	snprintf(buf, sizeof(buf), "tick %d\naround %c%c%c%c\n\n", tick_id, around[0], around[1], around[2], around[3]);
-	write(fd, buf, strlen(buf));
+	if (write(fd, buf, strlen(buf)) < (ssize_t) strlen(buf))
+		error = true;
 }

connection.h

@@ -8,6 +8,7 @@
 class connection {
 public:
 	int fd;
+	bool error;
 
 	connection(int fd_) : fd(fd_) {}
 

main.cc

@@ -47,6 +47,11 @@ main(int argc, char *argv[])
 
 		if (agent) {
 			agent->on_tick();
+			if (agent->conn && agent->conn->error) {
+				delete agent;
+				agent = NULL;
+			}
+
 		} else {
 			int cfd = accept(lfd, NULL, NULL);
 			if (cfd >= 0) {