48 lines
1.1 KiB
C
48 lines
1.1 KiB
C
#include <stdio.h>
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#include <stdlib.h>
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typedef struct {
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long long id;
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char *name;
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char *desc;
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int age;
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} Person;
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void test () {
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static int num = 0;
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num++;
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printf("Function test has been called %d times\n", num);
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}
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void test2() {
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// static variables defined in fuction can only be visited by this function.
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static int num = 0;
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num++;
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printf("Function test2 has been called %d times\n", num);
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}
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int main(int argc, char **argv) {
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// p is on stack, while q is on heap
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Person p;
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Person *q = (Person *)malloc(sizeof(Person));
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if (q == NULL) {
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printf("malloc fails\n");
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return -1;
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}
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// test();
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// test();
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// test2();
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// test2();
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/**
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* TODO: 看起来操作系统决定 malloc 申请的内存在哪里
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* Output on linux64 compiled by clang
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* addr of p: 0x5619048df2d0, addr of q: 0x7fb51f2e19e0
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* Output on win64 compiled by MinGW64 gcc
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* addr of p: 000000B0591FFB20, addr of q: 000000B0591FFB00
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*/
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printf("addr of p: %p, addr of q: %p\n", p, *q);
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free(q);
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return 0;
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}
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