CR LF lp

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#include <stdio.h>
#include <stdlib.h>
char* menu[] = {
	"a - add new record",
	"d = delete record",
	"q - quit",
	NULL,
};
// int func(int a[]) // a is a pointer to the first element of an array
// int func(int* a)  // is the same as the above one
// so I think the below one is equal to char** choices);
// int getchoice(char* greet, char* choices[]);
int getchoice(char* greet, char** choices);
int main()
{
	int choice = 0;
	do
	{
		choice = getchoice("please select an action", menu);
		printf("you have chosen: %c/n", choice);
	} while(choice != ‘q‘);
	exit(0);
}
int getchoice(char* greet, char** choices)
// int getchoice(char* greet, char* choices[])
{
	int chosen = 0;
	int selected;
	char** option;
	do {
		printf("choice: %s/n", greet);
		option = choices;
		while (*option)
		{
			printf("%s/n", *option);
			option++;
		}
		// when prog running, when user types ‘a‘ and Enter key, prog see ‘a‘ and
	   	// LF(‘/n‘)(10), not the character CR‘/r‘(13), unix and linux use a single
		// LF as the end of a line not like in windows it use both the two characters
		// but still strange happens, this program runs very well in both linux and 
		// windows OS.
		do // if I typed ‘a‘ and Enter in shell bash, there will be two characters in
		{  // buffer, character ‘a‘(97) and character ‘/n‘(10),
			selected = getchar();
		} while (selected == ‘/n‘); // discard the ‘/n‘
		option = choices;
		while (*option)
		{
			if (selected == *option[0])
			{
				chosen = 1;
				break;
			}
			option++;
		}
		if (!chosen)
		{
			printf("incorrect choice, select again/n");
		}
	} while (!chosen);
	return selected;
}

CR LF lp

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原文地址：http://www.cnblogs.com/sunyongjie1984/p/4258951.html