c - 简单的 C 代码总是崩溃

Question

这就是我所做的代码:

#include <stdio.h>
#include <stdlib.h>

int main()
{
char playerName;
int playerAge;

printf("What's your name, and your age?\nYour name: ");
scanf("%s\n", playerName);
printf("Your age: ");
scanf("%d\n", &playerAge);
printf("Okay %s, you are %d years old!", playerName, playerAge);

return 0;
}

每次我运行它时，输入我的名字后它都会崩溃，我不知道如何修复它。关闭时会出现以下 3 件事:

format '%s' expects argument of type 'char *', but argument 2 has type 'int' [-Wformat]|

format '%s' expects argument of type 'char *', but argument 2 has type 'int' [-Wformat]|

'playerName' is used uninitialized in this function [-Wuninitialized]|

我的错误是什么？

Answer 1

scanf("%s\n", playerName); 错误，因为 %s 调用 char* 数据，但 这里的playerName是类型char。

您必须将 playerName 设置为字符数组并设置输入的最大长度以避免缓冲区溢出。

#include <stdio.h>
#include <stdlib.h>

int main(void)
{
    char playerName[1024];
    int playerAge;

    printf("What's your name, and your age?\nYour name: ");
    scanf("%1023s\n", playerName); /* max length = # of elements - 1 for terminating null character */
    printf("Your age: ");
    scanf("%d\n", &playerAge);
    printf("Okay %s, you are %d years old!", playerName, playerAge);

    return 0;
}