A discussion on exercise#1 in class

Software Testing_1b-rev Page17

Exercise#1

Code content:

#include <stdio.h>int main (void) {     char buff[];      memset (Buff,0,sizeof(buff));     Gets (buff);       is [%s]\n ", buff);      return 0 ;   }

Is there a problem with this piece of code ...

As far as I can guess, there is no grammatical problem with the code in this job assigned by the teacher. So, the problem should be at the data level.

The Get () function is a function that reads a string from a standard input device, but it can read indefinitely without judging the upper bound to end the read with a carriage return. Therefore, you cannot limit the size of the number of characters you enter. A child buff is defined as an array of characters with a capacity of only 10, and when the input exceeds the upper bound, the program overflows.

A bit of code testing was done through Codeblocks: (converting code to C + +, although this is not scientific, but in order to avoid the use of C language inconvenient ...) Well, you know! ）

The code is as follows:

#include <iostream>#include<stdio.h>#include<string.h>using namespacestd;intMain () {Charbuff[Ten]; memset (Buff,0,sizeof(Buff));     Gets (buff); cout<<"The buffer entered is"<<Buff; return 0;}

Obviously, when the input data overflows, the program is forced to stop running.

A discussion on exercise#1 in class