Usage of format control %1!d! RRS feed

  • 问题

  • Hello everyone,

    Recently, I came across a kind of format control that I never saw before. 

    printf("Data recv failed (%1!d!)。\n\0", WSAGetLastError());

    What's the meaning of ‘!’?

    Thanks in advance!

    2015年10月9日 9:59


  • Hi,

    Where did you see this format? What result will you get if you write like this?

    Could you please show the whole demo code here?

    I write a simple demo to test this format with printf, it will not print the variable we want.

    #include "stdafx.h"
    #include <iostream>
    using namespace std;
    int _tmain(int argc, _TCHAR* argv[])
    	int d = 10;
    	return 0;

    The result is:

    So, in my opinion, this is incorrect format for printf. More about valid format for printf, you can refer to this link.


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    2015年10月12日 9:34