Re: WaitForSingleObject on Console not working???

"Tom Widmer [VC++ MVP]" <>
Thu, 13 Jul 2006 11:08:01 +0100
<#2Yu6QmpGHA.1440@TK2MSFTNGP03.phx.gbl> wrote:

How can I know if there is input or not from keyboard in console
application? I want to flush buffer to screen every second.

In Unix, select( ) with stdin and timeout can work well( return timeout
every second ), but in Windows, stdin is NOTSOCK, hence select won't

In Windows, WaitForSingleObject( stdinHandle, 1000 ) will return
"WAIT_OBJECT_0" when waiting for input.

How come the following always goes into "WAIT_OBJECT_0"?

Because there is some input on the handle at startup (probably a
FOCUS_EVENT_RECORD), and until you read that, wait calls will return

What could I do? Is there any way to use select( ) in Windows with


Try playing with this:
#include <windows.h>
#include <stdio.h>

int main()
    static HANDLE stdinHandle;
    // Get the IO handles
    // getc(stdin);
    stdinHandle = GetStdHandle(STD_INPUT_HANDLE);

    while (1)
        DWORD rc = WaitForSingleObject(stdinHandle, 1000);

        if( rc == WAIT_TIMEOUT )
        else if( rc == WAIT_ABANDONED )
        else if( rc == WAIT_OBJECT_0 )
            INPUT_RECORD r[512];
            DWORD read;
            ReadConsoleInput(stdinHandle, r, 512, &read);
            printf("Read: %d", read);
        else if( rc == WAIT_FAILED )
            printf("Error:%d.", GetLastError());

    return 0;

Tom (again!)

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