您好我在Linux平台下的c中有以下代码
#include <stdio.h>
#include <string.h>
int main(void) {
unsigned char client_id[8];
char id[17] = "00000001";
sscanf(id,"%02X%02X%02X%02X", &client_id[0], &client_id[1], &client_id[2], &client_id[3]);
printf("%02X%02X%02X%02X", client_id[0], client_id[1], client_id[2], client_id[3]);
}
当我运行此代码时,我得到输出
00000001
但有以下警告
> test.c: In function ‘main’: test.c:7:1: warning: format ‘%X’ expects
> argument of type ‘unsigned int *’, but argument 3 has type ‘unsigned
> char *’ [-Wformat=]
> sscanf(id,"%02X%02X%02X%02X",&client_id[0],&client_id[1],&client_id[2],&client_id[3]);
> ^ test.c:7:1: warning: format ‘%X’ expects argument of type ‘unsigned
> int *’, but argument 4 has type ‘unsigned char *’ [-Wformat=]
> test.c:7:1: warning: format ‘%X’ expects argument of type ‘unsigned
> int *’, but argument 5 has type ‘unsigned char *’ [-Wformat=]
> test.c:7:1: warning: format ‘%X’ expects argument of type ‘unsigned
> int *’, but argument 6 has type ‘unsigned char *’ [-Wformat=]
警告很明显,但我该如何删除?
我不想使用
-Wno指针-符号
我应该使用sprintf
或sscanf
中的任何更改吗?
答案 0 :(得分:3)
您需要告诉sscanf
参数属于char
类型。这是通过将hh
修饰符放在X
格式说明符之前完成的:
sscanf(id,"%02hhX%02hhX%02hhX%02hhX",&client_id[0],&client_id[1],&client_id[2],&client_id[3]);