C Programming - Format Strings are Important!!

Guess, What will be the output?


#include < stdio.h >

int main(int argc, char *argv[])
{
 int i=10;
 int *j=&i;
 printf("aaa%n\n");
 printf("%d\n",i);
}

I ran this program on .NET platform with optimization disabled, it should be portable across all other platforms also.

Labels: C

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# Anonymous 10:44 pm
>>printf("aaa%n\n");<<

%n expects address of variable where the number of characters printed successfully on the screen in stored..Since u havent passed any pointer arguments here the program will crash.

try
int x;
printf("aaa%n\n",&x);
# Anonymous 2:04 am
thatz Ok! But how does &x gets passed to the function printf it will be pushed on to the stack. So the program that he wrote as we are not passing an argument it will take the previous stack elements value.

Please do run that program and see, don't say that it will crash boy!
# Anonymous 4:25 am
Since he didnt passed enough arguments to the printf function the behaviour is undefined..
When i tried the same code in GCC it crashed..