Thread: undefined symbols

Working on a mac and getting an 'undefined symbols' error when I try to compile this push pop program. I don't see a problem in my code; I'm wondering if it could be a problem with the gcc version I have? If anyone can help it would be most appreciated

Here's my code:

Code:

#include <stdio.h>
#include <stdlib.h>		/* for atof() */

#define MAXOP	100		/* max size of operand or operator */
#define NUMBER	'0'		/* signal that a number was found */

int getop (char []);
void push (double);
double pop (void);

/* reverse Polish calculator */
main()
{
	int type;
	double op2;
	char s[MAXOP];
	
	while ((type = getop(s)) != EOF)
	{
		switch (type)
		{
		case NUMBER:
			push (atof(s));
			break;
		case '+':
			push(pop() + pop());
			break;
		case '*':
			push(pop() * pop());
			break;
		case '-':
			push(pop() - op2);
			break;
		case '/':
			op2 = pop();
			if (op2 != 0.0)
				push(pop() / op2);
			else
				printf("error: zero divisor\n");
			break;
		case '\n':
			printf("\t%.8g\n", pop());
			break;
		default:
			printf("error: unknown command %s\n", s);
			break;
		}
	}
	return 0;
}

Here's my error:

Code:

/usr/bin/ld: Undefined symbols:
_getop
_pop
_push
collect2: ld returned 1 exit status

Thanks, I had a feeling that might have been the case...I added in the missing functions and it works now

I think that's his attempt at being modest by doubting his own ability.