Problem while writing sketch for GSM module sim800 I wanted to my GSM to recieve SMSs. I have written a sketch for it. But while verifying the sketch an error pops out in this part:

if (sms.available()) {
      sms.remoteNumber(senderNnumber, 20);
      if (senderNumber == "09432167015") {
        c = sms.read();
      if (c == "yes") {
          alarm_police();
          }
        }
      }   
The error message:


  Arduino: 1.6.5 (Windows 8.1), Board: "Arduino/Genuino Uno"
  
  GuardDog_v2.5.ino: In function 'void loop()':
  GuardDog_v2.5:201: error: 'senderNnumber' was not declared in this scope
  GuardDog_v2.5:204: error: ISO C++ forbids comparison between pointer and >integer [-fpermissive]
  'senderNnumber' was not declared in this scope
  
  This report would have more information with
   "Show verbose output during compilation"
   enabled in File > Preferences.


I have checked the receiving sms example and have written the sketch according to the example.I need help regarding this error and how to fix it
You misspelled the variable senderNumber. Correct it. Also you aren't reading the SMS properly or comparing the phone numbers properly. Your code should be like this (using the examples):

#define MAX_MSG 50

char senderNumber[20];
char sms_buf[MAX_MSG];   // a buffer for your sms, max len = 50

if (sms.available()) {    // this part should be in loop()
  sms.remoteNumber(senderNumber, 20);
  if (strcmp(senderNumber, "09432167015") == 0) { // compare numbers
    while (sms.available() == 0);   // wait for a char
    char i = 0;
    while (i &lt; MAX_MSG - 1){    // till max len is reached; 1 byte for null
      c = sms.read();
      if (c == '\0')  // assuming the modem terminates sms with null
        break;
      sms_buf[i++] = c;   // write char to the buffer
      while (sms.available() == 0);   //wait for a char
    }
    sms_buf[i] = 0;   // terminate the string, just in case
    if (strstr(sms_buf, "yes") != NULL)  // look for 'yes' in buffer
      alarm_police();
  }
}