What is this error when I try to compile a simple C program in gcc?

[mstshtml]

ok, so i am somewhat new to linux and have VERY basic knowledge of programming. I am trying to learn Objective-C and here is this sample program using classes.

// Program to work with fractions - class version
#import <stdio.h>
#import <objc/Object.h>

//--------------@interface section-------------

@interface Fraction: Object
{
	int numerator;
	int denominator;
}

-(void) print;
-(void) setNumerator: (int) n;
-(void) setDenominator: (int) d;

@end

//-----------@implimentation section--------------------

@implementation Fraction;
-(void) print
{
	printf (" %i/%i ", numerator, denominator);
}

-(void) setNumerator: (int) n
{
	numerator = n;
}

-(void) setDenominator: (int) d
{
	denominator = d;
}

@end

//-------------program section----------------

int main (int argc, char *argv[])
{
	Fraction *myFraction;

// Create an instance of a Fraction

	myFraction = [Fraction alloc];
	myFraction = [myFraction init];

// Set Fraction to 1/3
	[myFraction setNumerator: 1];
	[myFraction setDenominator: 3];

// Display the fraction using the print method

	printf ("The value of myFraction is:");
	[myFraction print];
	printf ("\n");
	[myFraction free];

	return 0;
}

When I try and compile it I get this:

[mstshtml@localhost prog3]$ gcc main.m -o prog3-2
/tmp/ccu7A1rE.o: In function `main':
main.m:(.text+0x7b): undefined reference to `objc_get_class'
main.m:(.text+0x8b): undefined reference to `objc_msg_lookup'
main.m:(.text+0xad): undefined reference to `objc_msg_lookup'
main.m:(.text+0xd5): undefined reference to `objc_msg_lookup'
main.m:(.text+0xfe): undefined reference to `objc_msg_lookup'
main.m:(.text+0x136): undefined reference to `objc_msg_lookup'
/tmp/ccu7A1rE.o:main.m:(.text+0x164): more undefined references to `objc_msg_lookup' follow
/tmp/ccu7A1rE.o: In function `__objc_gnu_init':
main.m:(.text+0x18e): undefined reference to `__objc_exec_class'
/tmp/ccu7A1rE.o:(.data+0x2e8): undefined reference to `__objc_class_name_Object'
collect2: ld returned 1 exit status

can someone help me with whats going on with this error?
thank
-steve

[i92guboj]

I have exactly zero experience with objetive C, but, it's a linker error. You probably have to include the path to the compiled object library. I don't know what that is called. The command would be something like:

gcc main.m -o prog3-2 -L/path/to/Object/lib