fix(client): Make flush() call clear() and deprecate it (espressif#10242)

This is a compromise for issues caused by espressif#9453

Author: me-no-dev

libraries/Network/src/NetworkClient.cpp

@@ -369,7 +369,9 @@ int NetworkClient::read() {
  return data;
 }
 
-void NetworkClient::flush() {}
+void NetworkClient::flush() {
+ clear();
+}
 
 size_t NetworkClient::write(const uint8_t *buf, size_t size) {
  int res = 0;

libraries/Network/src/NetworkClient.h

@@ -56,6 +56,7 @@ class NetworkClient : public ESPLwIPClient {
  size_t write(const uint8_t *buf, size_t size);
  size_t write_P(PGM_P buf, size_t size);
  size_t write(Stream &stream);
+ [[deprecated("Use clear() instead.")]]
  void flush(); // Print::flush tx
  int available();
  int read();

libraries/Network/src/NetworkUdp.cpp

@@ -288,7 +288,9 @@ size_t NetworkUDP::write(const uint8_t *buffer, size_t size) {
  return i;
 }
 
-void NetworkUDP::flush() {}
+void NetworkUDP::flush() {
+ clear();
+}
 
 int NetworkUDP::parsePacket() {
  if (rx_buffer) {

libraries/Network/src/NetworkUdp.h

@@ -64,6 +64,7 @@ class NetworkUDP : public UDP {
  int endPacket();
  size_t write(uint8_t);
  size_t write(const uint8_t *buffer, size_t size);
+ [[deprecated("Use clear() instead.")]]
  void flush(); // Print::flush tx
  int parsePacket();
  int available();