[問題] 指標傳遞問題
開發平台(Platform): (Ex: Win10, Linux, ...)
LINUX
編譯器(Ex: GCC, clang, VC++...)+目標環境(跟開發平台不同的話需列出)
GCC
問題(Question):
宣告一個struct
typedef struct {
uint8_t var_a;
uint8_t var_b;
} test_entry_t;
宣告一個指標
test_entry_t *p_entry
宣告一個function
function testF(test_entry_t *p_entry){
uint8_t var1 = 0x01
uint8_t var2 = 0x02
p_entry->var_a = var1
p_entry->var_b = var2
}
我嘗試用以下方是來call此function
int main(){
test_entry_t *p_entry
testF(&p_entry);
printf("0x%02X\n", p_entry->var_a);
printf("0x%02X\n", p_entry->var_b);
預計輸出結果
0x01
0x02
但是我印出來卻是空的!
想請問各位大大我這段code哪裡寫錯了!
感謝
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※ 編輯: blueguan (1.164.192.107), 12/02/2016 19:13:00
※ 編輯: blueguan (1.164.192.107), 12/02/2016 19:13:38
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12/02 19:13, , 1F
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※ 編輯: blueguan (1.164.192.107), 12/02/2016 19:46:48
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