模拟实现C语言库函数strcat

首先，我们看一下MSDN中对它的定义，函数参数，返回值
strcat
（定义）Append a string.

（函数参数）char *strcat( char *strDestination, const char *strSource );

（返回值）Each of these functions returns the destination string (strDestination). No return value is reserved to indicate an error.
接下来看一下代码实现

#include<stdio.h>
#include<assert.h>
#include<windows.h>
char* my_strcut(char* p,const char* q)
{
    assert(p != NULL);
    assert(q != NULL);
    char* str = p;
    while(*p)
    {
        p++;
    }
    while (*p++ = *q++)
    {
        ;
    }
    return str;
}
int main()
{
    char arr[20] = "hello  ";
    my_strcut(arr, "bit");
    printf("%s",arr);
    system("pause");
    return 0;
}