C语言完美演绎7-14

/* 范例：7-14 */

#include <stdio.h>

#include <string.h>

int main(void)

{

/* 设定stpcpy、strcpy、strncpy函数的参数dest */

char mystpcpy[10];

char mystrcpy[10];

char mystrncpy[10];

char bigmystrncpy[10];

/* 设定stpcpy、strcpy、strncpy函数的参数src */

char *str1 = "abcdefghi";

char *str2= "tiger is good";

/* 用四个指针变量(a、b、c、d)接收stpcpy、strcpy、strncpy函数的返回值 */

char *a,*b,*c,*d;

a = stpcpy(mystpcpy, str1);

b = strcpy(mystrcpy, str1);

c = strncpy(mystrncpy, str1,3); /* 稍后再将'\0'加到所复制的字符串结尾 */

d = strncpy(bigmystrncpy, str2,13);

mystrncpy[3]='\0'; /* 加上'\0'，以保持字符串的完整性 */

/* 输出mystpcpy[10]、mystrcpy[10]、mystrncpy[10] */

printf("这是用stpcpy复制%s\n", mystpcpy);

printf("这是用strcpy复制%s\n", mystrcpy);

printf("这是用strncpy复制%s\n", mystrncpy);

a=a-5; /* 指针变量a指向mystpcpy的结尾('\0')，将其往前推5个字符 */

/* 输出四个指针变量(a、b、c、d) */

printf("\na=%s,\t&a=%u\t&mystpcpy=%u",a,(void*) a,mystpcpy);

printf("\nb=%s,\t&b=%u\t&mystrcpy=%u",b,(void*) b,mystrcpy);

printf("\nc=%s,\t\t&c=%u\t&mystrncpy=%u",c,(void*) c,mystrncpy);

printf("\nd=%s,\t&d=%u\t&bigmystrncpy=%u",d,(void*) d,bigmystrncpy);

getchar();

return 0;

}

程序执行结果：

这是用stpcpy复制abcdefghi

这是用strcpy复制abcdefghi

这是用strncpy复制dbc

a=efghi, &a=6618620 &mystpcpy=6618616

b=abcdefghi, &b=6618604 &mystrcpy=6618604

c=dbc, &c=6618592 &mystrncpy=6618592

d=tiger is goodbc, &d=6618580 &bigmystrncpy=6618580