C语言 复制字符串 malloc

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

typedef void(*str_cpy_slk)(char *name);
void test(str_cpy_slk cb);
void call_back(char *name);

char *test_name = NULL;
int main(void)
{
　　test(call_back);

　　printf("name:%s\n", test_name);

　　return 0;
}

void test(str_cpy_slk cb)
{
　　char myname[8] = {0};
　　snprintf(myname, sizeof(myname), "%s", "slk");
　　printf("myname:%s\n", myname);
　　cb(myname);
}

void call_back(char *name)
{
　　test_name = name;
　　printf("test_name:%s\n", test_name);
}

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

typedef void(*str_cpy_slk)(char *name);
void test(str_cpy_slk cb);
void call_back(char *name);

char *test_name = NULL;
int main(void)
{
　　test(call_back);

　　printf("name:%s\n", test_name);

　　free(test_name);

　　return 0;
}

void test(str_cpy_slk cb)
{
　　char myname[8] = {0};
　　snprintf(myname, sizeof(myname), "%s", "slk");
　　printf("myname:%s\n", myname);
　　cb(myname);
}

void call_back(char *name)
{
　　test_name = (char *)malloc(strlen(name) + 1);
　　snprintf(test_name, strlen(name) + 1, "%s", name);
　　printf("test_name:%s\n", test_name);
}