# 标准库string.h函数strcat()

**函数原型**

```c
char * strcat(char * destination, const char * source);
```

**说明**

将两个字符串拼接。具体为三步：将destination的末尾 `\0` 删除；将后一个source连同后面的`\0` 连接到destination后面。

**参数**

```
destination: C-style指针
source: C-style指针
```

**返回值**

返回destination的指针。

**实例**

```c
#include <stdio.h>
#include <string.h>

int main(){
    char str[80];
    strcpy(str, "these ");
    strcat(str, "strings ");
    strcat(str, "are ");
    strcat(str, "concatenated.");
    puts(str);
    return 0;
}
```




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