play_again0.c

unix linux 编程实践源代码

/* play_again0.c
 *	purpose: ask if user wants another transaction
 *	 method: ask a question, wait for yes/no answer
 *	returns: 0=>yes, 1=>no
 *	 better: eliminate need to press return 
 */
#include	<stdio.h>
#include	<termios.h>

#define	QUESTION	"Do you want another transaction"

int get_response( char * );

int main()
{
	int	response;

	response = get_response(QUESTION);	/* get some answer	*/
	return response;
}
int get_response(char *question)
/*
 * purpose: ask a question and wait for a y/n answer
 *  method: use getchar and ignore non y/n answers
 * returns: 0=>yes, 1=>no
 */
{
	printf("%s (y/n)?", question);
	while(1){
		switch( getchar() ){
			case 'y': 
			case 'Y': return 0;
			case 'n': 
			case 'N': 
			case EOF: return 1;
		}
	}
}