因專案需要多程序共享資源訪問....
#include #include #include typedef struct titem;
typedef structtbank;
typedef struct tbankctrl;
static titem g_titem = ,
, ,, ,
};static tbank g_tbank = , };
static tbankctrl g_bankctrl;
extern "c"
tbankctrl *getbankctrl()
int add(int a,int b)
int sub(int a, int b)
int mul(int a, int b)
int div1(int a, int b)
}
2. 主原始碼編譯編譯
#include #include #include //動態鏈結庫路徑
#define lib_caculate_path "./libdync.so"
typedef struct titem;
typedef structtbank;
typedef struct tbankctrl;
//函式指標
typedef int (*cac_func)(int, int);
typedef tbank * (*cac_func_bank)();
typedef tbankctrl * (*cac_func_bank_ctrl)();
int main(int argc, char *ar**)
//清除之前存在的錯誤
dlerror();
//獲取乙個函式
*(void **) (&cac_func) = dlsym(handle, "add");
if ((error = dlerror()) != null)
printf("add: %d\n", (*cac_func)(2,7));
cac_func = (cac_func)dlsym(handle, "sub");
printf("sub: %d\n", cac_func(9,2));
cac_func = (cac_func)dlsym(handle, "mul");
printf("mul: %d\n", cac_func(3,2));
cac_func = (cac_func)dlsym(handle, "div1");
printf("div: %d\n", cac_func(8,2));
#if 0
cac_func_bank = (cac_func_bank)dlsym(handle, "getbank");
ptbank = cac_func_bank();
for (ibankidx = 0; ibankidx < 2; ibankidx++) }
//關閉動態鏈結庫
//dlclose(handle);
exit(exit_success);
}
add was used.
add: 9
sub was used.
sub: 7
mul was used.
mul: 6
div1 was used.
div: 4
bankname: bank-a, item: item-a, id=1
bankname: bank-a, item: item-b, id=2
bankname: bank-a, item: item-c, id=3
bankname: bank-a, item: item-d, id=4
bankname: bank-a, item: item-e, id=5
bankname: bank-b, item: item-a, id=1
bankname: bank-b, item: item-b, id=2
bankname: bank-b, item: item-c, id=3
bankname: bank-b, item: item-d, id=4
bankname: bank-b, item: item-e, id=5
結果驗證ok，能正常使用動態庫；
4. 主應用程式不修改，修改動態庫的bank配置資料如下
static titem g_titem = ,
, ,, ,
//以下值是新增加的
, ,, };
add was used.
add: 9
sub was used.
sub: 7
mul was used.
mul: 6
div1 was used.
div: 4
bankname: bank-a, item: item-a, id=1
bankname: bank-a, item: item-b, id=2
bankname: bank-a, item: item-c, id=3
bankname: bank-a, item: item-d, id=4
bankname: bank-a, item: item-e, id=5
bankname: bank-a, item: item-f, id=6
bankname: bank-a, item: item-g, id=7
bankname: bank-a, item: item-h, id=8
bankname: bank-b, item: item-a, id=1
bankname: bank-b, item: item-b, id=2
bankname: bank-b, item: item-c, id=3
bankname: bank-b, item: item-d, id=4
bankname: bank-b, item: item-e, id=5
bankname: bank-b, item: item-f, id=6
結果驗證ok，能正常執行。
5. 總結
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