Fixed borken read

grbl_communication.cpp

@@ -83,7 +83,12 @@ void grbl::tcp_transport::worker() {
 
             // anything to read?
             auto read_bytes = read(fd, buffer, 200);
-            if (read_bytes > 0) {
+            if (read_bytes == -1 && (errno == EWOULDBLOCK || errno == EAGAIN)) {
+                // do nothing
+            } else if (read_bytes == -1) {
+                std::cerr << "Failed while reading." << std::endl;
+                close();
+            } else {
                 for (int i = 0; i < read_bytes; i++) {
                     auto is_eol = buffer[i] == '\r' || buffer[i] == '\n';
                     if (is_eol) {
@@ -98,7 +103,7 @@ void grbl::tcp_transport::worker() {
             }
 
             // give some time to others
-            std::this_thread::sleep_for(std::chrono::milliseconds(100));
+            std::this_thread::sleep_for(std::chrono::milliseconds(1));
         }
     }
 }