Thread: Segmentation faults when trying to modify a character array

Hello

I've initialized a character array in my main, and passed it onto one of my functions convertToPostfix(char infix[], char postfix[]). It isn't a constant read only array (constant char*) ive explicitly initialized it to char postfix[] = "";

Code:

if ((nextChar > 47) && (nextChar < 58)){    //if its a digit
        postfix[++postfixIndex] = nextChar;
        while (infix[i + 1] > 47 && infix[i + 1] < 58){
            nextChar = infix[++i];
            postfix[++postfixIndex]=nextChar;//segmentation fault when assigning from infix to postfix**
                        }

please explain what I'm doing wrong....D: