pressing 'q' or non-numeric char to exit loop/program

Hi, this is a simple temperature converter (Fahrenheit to Celsius to
Kelvin).  Using gcc 4.0.

The user is supposed to enter q or any other non-character to exit the
program.

Problem with this code:
I enter 'q' as soon as the program starts. It hangs.
Then run it again. Enter a number, it executes fine. But when I enter
q, it repeats last number and it doesn't 'pay attention' to the letter
entered.


Any ideas on how can I fix it? thanks in advance.

#include <stdio.h>

const double F_TO_CELS_ONE_EIGHT = 1.8;
const double F_TO_CELS_THIRTYTWO = 32.0;
const double C_TO_KELVIN = 273.16;

void Temperatures(double f_temp);

int main(void){

	double f_temp;
	char quit;


	while (quit != "q"){
		printf("Enter temperature in Fahrenheit (q to quit): ");
		quit = getchar();
		scanf("%lf", &f_temp);
		Temperatures(f_temp);
	}
	printf("\nbye!");
	return 0;
}

void Temperatures(double f_temp){

	double celsius, kelvin;

	celsius = (F_TO_CELS_ONE_EIGHT * f_temp) + F_TO_CELS_THIRTYTWO;
	kelvin = celsius + C_TO_KELVIN;

	printf("Fahrenheit degrees: %.2f\n", f_temp);
	printf("Celsius degrees: %.2f\n", celsius);
	printf("Kelvin degrees: %.2f\n", kelvin);


}
-- 
comp.lang.c.moderated - moderation address: clcm@[EMAIL PROTECTED]
 -- you must
have an appropriate newsgroups line in your header for your mail to be
seen,
or the newsgroup name in square brackets in the subject line.  Sorry.