SIM800L AT Commands

Hi all,
can you help me to get whole text in HTTP response:

void gprs_send(String data) {  
  int d = 400;
  Serial.println("Send start");
  Serial.println("setup url");
  GSMport.println("AT+HTTPPARA=\"URL\",\"http://arduinodev.com/datetime.php?a=" + data + "\"");
  delay(d * 2);
  Serial.println(ReadGSM());
  delay(d);
  Serial.println("GET url");
  GSMport.println("AT+HTTPACTION=0");
  delay(d * 2);
  Serial.println(ReadGSM());
  delay(d);

  GSMport.println("AT+HTTPREAD");
  delay(d * 2);
  Serial.println(ReadGSM());
  delay(d);
  Serial.println("Send done");
}

String ReadGSM() {  
  int c;
  String v;
  while (GSMport.available()) {  
    c = GSMport.read();
    v += char(c);
    delay(10);
  }
  return v;
}

In browser we cen get next:

20160402183716

But in Serial I get next 9 chars:

201604021

Send start
setup url
AT+HTTPPARA="URL","http://arduinodev.com/datetime.php?a=0"

OK
GET url
AT+HTTPACTION=0

OK

+HTTPACTION: 0,200,14
AT+HTTPREAD

+HTTPREAD: 14
201604021
Send done

How to get whole url response?

Thank you in advance.

How to get whole url response?

Wait stupidly longer between characters. Try:

String ReadGSM() { 
  int c;
  String v;
  while (GSMport.available()) { 
    c = GSMport.read();
    v += char(c);
    delay(10000);
  }
  return v;
}