try ... catch not working

Question

int main (int argc, const char * argv[]) { <br>

NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];

int a1,b1,c1;
@try {      
    NSLog(@"Enter numerator: ");
    scanf("%i",&a1);
    NSLog(@"Enter denomenator: ");
    scanf("%i",&b1);
    c1 = a1/b1;
    NSLog(@"%i",c1);
}
@catch (NSException * e) {
    NSLog([e name]);
    NSLog([e description]);
    NSLog([e reason]);
}
@finally {
    NSLog(@"inside finally block");
}
[pool drain]; 

return 0; 

}   

Here if i enter value of a1=10, b1=0, then there should be exception generated, so statement within catch block will supposed to be execute. But it doesn't. Program crashed. Try..Catch doesn't work in this case ......Looks like i am doing something wrong...

Answer 1

try/catch will only work for Obj-C exceptions that are thrown. They are quite high-level constructs. This is probably different from the Java try/catch blocks, that let you catch almost everything.

Answer 2

You are seeing the floating point exception which is caused by C code (c1 = a1/b1). This is not wrapped in a NSException.

If you want to go through the catch block, you can replace your FPE code with

[[NSString string] setValue:@"" forKeyPath:@"KP"];

which will trigger a NSUnknownKeyException.