sprintf ?

Projects Programming
7

bhavasarbhagyesh:
**HEY GUYS I GOT THE ANSWER FOR, CONVERT FLOATING VALUES IN STRING USING SPRINTF(); FUNCTION **

double temp = 55.55;
char buffer[4];

sprintf(buffer, "%02.02f", temp);

ssd1306_set_cursor(15, 26);
ssd1306_putstring(buffer);
ssd1306_display();

OUTPUT:
55.55

You think? You declare a 4 character array, then expect 6 characters (including the terminating null) to fit in it, for one.

And why does this print "?":-

void setup()
{
    Serial.begin(115200);
    double temp = 55.55;
    char buffer[4];
    sprintf(buffer, "%02.02f", temp);
    Serial.println(buffer);                  // Prints "?"
}

void loop(){}

Also why does this print "2":-

void setup()
{
    Serial.begin(115200);
    double temp = 55.55;
    char buffer[4];
    sprintf(buffer, "%02.02f", temp);
    Serial.println(strlen(buffer));        // Prints "2"
}

void loop(){}