While there is not command line flag to suppress the dialog, since OK is the default button on the dialog you could simulate a Return keypress after calling repllog like this:
CreateProcess(_T("\\windows\\repllog.exe"), _T("remote"), NULL, NULL, false, 0, NULL, NULL, NULL, NULL);
keybd_event(VK_RETURN, 0, KEYEVENTF_SILENT, 0);
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Chris Tacke, eMVP
Applied Data Support