在函数中更改指针的值

我想在函数中更改变量的值。 我的代码是这样的：

void change(char *buf){ char str = "xxxxxxx"; *buf = &str; } int main(){ char *xxx = NULL; change(xxx); } 

当我用valgrind调试时，它说：

 ==3709== Invalid write of size 1 ==3709== at 0x80483CA: change (test.c:5) ==3709== by 0x80483E5: main (test.c:10) ==3709== Address 0x0 is not stack'd, malloc'd or (recently) free'd ==3709== ==3709== ==3709== Process terminating with default action of signal 11 (SIGSEGV) ==3709== Access not within mapped region at address 0x0 ==3709== at 0x80483CA: change (test.c:5) ==3709== by 0x80483E5: main (test.c:10) 

谁能帮我？ 我是C的新人….

Answer 1

使用指针指针：

 void change(char **buf) { *buf = "xxxxxxx"; } int main(void) { char *xxx = NULL; change(&xxx); }