Thread: popen()

  1. #1
    int x = *((int *) NULL); Cactus_Hugger's Avatar
    Join Date
    Jul 2003
    Banks of the River Styx


    I'm trying to do some parsing on netstat's output, but this is proving rather difficult...:

    So far, popen() has me baffled. As far as I can tell from the snippit below, popen is returning NULL, and errno is set to zero. (Which makes no sense.) What is going on here?

    	ph = popen("netstat -e", "r");
    		sprintf(err, "Error is %d. ph = %d\n", errno, ph);
    		MessageBox(HWND_DESKTOP, "popen failed.", "popen", MB_OK);
    		MessageBox(HWND_DESKTOP, err, err, MB_OK);
    (function continues..., or would, if popen() would succeed...)
    Since all I really care about is the bytes sent & recv'd... is there an easier way to get those numbers? Some API call I know nothing about?
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  2. #2
    and the hat of int overfl Salem's Avatar
    Join Date
    Aug 2001
    The edge of the known universe
    Perhaps the health warning here explains.
    Note The _popen function returns an invalid file handle, if used in a Windows program, that will cause the program to hang indefinitely. _popen works properly in a Console application. To create a Win
    > Some API call I know nothing about?
    Almost certainly, probably the ones netstat uses itself.
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
    If at first you don't succeed, try writing your phone number on the exam paper.

  3. #3
    Yes, my avatar is stolen anonytmouse's Avatar
    Join Date
    Dec 2002
    You could use GetIfTable, which will give you the number of bytes sent and received for each interface. Netstat appears to use GetIpStatsFromStackEx, which is undocumented.

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