Don't need maintain in buffer dump

Signed-off-by: Sara Damiano <sdamiano@stroudcenter.org>

src/TinyGsmClientSIM7000.h

@@ -548,8 +548,10 @@ class TinyGsmSim7000 : public TinyGsmModem<TinyGsmSim7000>,
     //  ^^ Requested number of data bytes (1-1460 bytes)to be read
     int16_t len_confirmed = streamGetIntBefore('\n');
     // ^^ Confirmed number of data bytes to be read, which may be less than
-    // requested. 0 indicates that no data can be read. This is actually be the
-    // number of bytes that will be remaining after the read
+    // requested. 0 indicates that no data can be read.
+    // SRGD NOTE:  Contrary to above (which is copied from AT command manual)
+    // this is actually be the number of bytes that will be remaining in the
+    // buffer after the read.
     for (int i = 0; i < len_requested; i++) {
       uint32_t startMillis = millis();
 #ifdef TINY_GSM_USE_HEX

src/TinyGsmClientSIM800.h

@@ -457,12 +457,15 @@ class TinyGsmSim800
   }
 
   byte NTPServerSync(String server = "pool.ntp.org", byte TimeZone = 3) {
+    // Set GPRS bearer profile to associate with NTP sync
     sendAT(GF("+CNTPCID=1"));
     if (waitResponse(10000L) != 1) { return -1; }
 
+    // Set NTP server and timezone
     sendAT(GF("+CNTP="), server, ',', String(TimeZone));
     if (waitResponse(10000L) != 1) { return -1; }
 
+    // Request network synchronization
     sendAT(GF("+CNTP"));
     if (waitResponse(10000L, GF(GSM_NL "+CNTP:"))) {
       String result = stream.readStringUntil('\n');
@@ -520,8 +523,10 @@ class TinyGsmSim800
     //  ^^ Requested number of data bytes (1-1460 bytes)to be read
     int16_t len_confirmed = streamGetIntBefore('\n');
     // ^^ Confirmed number of data bytes to be read, which may be less than
-    // requested. 0 indicates that no data can be read. This is actually be the
-    // number of bytes that will be remaining after the read
+    // requested. 0 indicates that no data can be read.
+    // SRGD NOTE:  Contrary to above (which is copied from AT command manual)
+    // this is actually be the number of bytes that will be remaining in the
+    // buffer after the read.
     for (int i = 0; i < len_requested; i++) {
       uint32_t startMillis = millis();
 #ifdef TINY_GSM_USE_HEX

src/TinyGsmTCP.tpp

@@ -265,14 +265,11 @@ class TinyGsmTCP {
     // data that it wants from the socket even if it was closed externally.
     inline void dumpModemBuffer(uint32_t maxWaitMs) {
       TINY_GSM_YIELD();
-      rx.clear();
-      at->maintain();
       uint32_t startMillis = millis();
-      while (sock_available > 0 && (millis() - startMillis < maxWaitMs)) {
-        at->modemRead(TinyGsmMin((uint16_t)rx.free(), sock_available), mux);
+      do {
         rx.clear();
-        at->maintain();
-      }
+        at->modemRead(TinyGsmMin((uint16_t)rx.free(), sock_available), mux);
+      } while (sock_available > 0 && (millis() - startMillis < maxWaitMs));
     }
 
     modemType* at;