Confusions about if statement and strcmp with Strings

Question

Here, I need some help in understanding the strings. I have a buff, which is flushed and then passed to a UART function. This buffer is now updated nad holding some value. I need to check the 5th byte of the buffer. What confuses me, I have written in code below. Please take a look.

int main()  
{  
  char buff[8];
  memset(buff,0,8);  

  /*  
       This buff is used by some UART function, and hence is updated by UART  
       This buff now holds some data. And now, I need to check the 5th byte it is holding.  
  */   

  if(buff[4]==0x04)  //will this work? or I need to use if(strcmp(buff[4],0x04))  ???
  {  
    //Do some functionality, for an example    
    printf("True");  
  }  
  else  
    printf("False");  

  return 0;  
}  

Answer 1

Your code is correct, yes.

Using strcmp() for this would only work if you know that the '\\x04' character is followed by a '\\0' string terminator. Since it looks like binary data, it would be very strange to use strcmp() .

You are not in any way comparing "strings", so using == is fine. In C, a "string" means "a (pointer to a) 0-terminated array of char ". That is not waht you're dealing with, so any lessons learned about how to deal with strings don't apply.