strncpy函数需要引用#include <string.h>头文件
函数原型:
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char *_Dest 是字符串的去向
char *_Source是字符串的来源
size_t_Count是复制字符串的大小
#include <stdio.h>
#include <string.h>
int main()
{
char arr[128] = { '\0' };
char str[128] = { '\0' };
int len = 0;
gets(arr);
len = strlen(arr);
strncpy(str,arr+4,len); example中arr+4指向e
puts(str);
return 0;
}
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如果arr中为 "abcdefg '\0' fadfg"
此时复制是"abcdefg "
也就是遇到'\0'结束
#include <stdio.h>
#include <string.h>
int main()
{
char arr[128] = { '\0' };
char str[128] = { '\0' };
int len = 0;
gets(arr);
len = strlen(arr);
strncpy(str,arr+4,5);
puts(str);
return 0;
}
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