问DirectFB教程无效参数
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提问于 2013-09-12 07:34:31

回答 1查看 1.7K关注 0票数 1

我似乎无法启动DirectFB，这样它就可以毫无问题地启动了。当我尝试在DFBCHECK (DirectFBCreate (&dfb))之后访问函数时，我会得到“无效参数”；我尝试从教程中运行简单的示例。代码如下：

 #include <stdio.h>
#include <unistd.h>
#include <directfb.h>

static IDirectFB *dfb = NULL;
static IDirectFBSurface *primary = NULL;
static int screen_width  = 0;
static int screen_height = 0;

#define DFBCHECK(x...)                                         \
  {                                                            \
    DFBResult err = x;                                         \
                                                               \
    if (err != DFB_OK)                                         \
      {                                                        \
        fprintf( stderr, "%s <%d>:\n\t", __FILE__, __LINE__ ); \
        DirectFBErrorFatal( #x, err );                         \
      }                                                        \
  }

int main (int argc, char **argv)
{
   int argx = 2;
   char *argData[] = {"self","--dfb:system=fbdev,disable-module=keyboard,disable-module=joystick,no-hardware",0};
   char **argPointer = argData;

   DFBSurfaceDescription dsc;
   DFBCHECK (DirectFBInit (&argx,&argPointer));
   DFBCHECK (DirectFBCreate (&dfb));
   DFBCHECK (dfb->SetCooperativeLevel (dfb, DFSCL_FULLSCREEN));
   dsc.flags = DSDESC_CAPS;
   dsc.caps  = DSCAPS_PRIMARY | DSCAPS_FLIPPING;
   DFBCHECK (dfb->CreateSurface( dfb, &dsc, &primary ));
   DFBCHECK (primary->GetSize (primary, &screen_width, &screen_height));
   DFBCHECK (primary->FillRectangle (primary, 0, 0, screen_width, screen_height));
   DFBCHECK (primary->SetColor (primary, 0x80, 0x80, 0xff, 0xff));
   DFBCHECK (primary->DrawLine (primary,
                                  0, screen_height / 2,
                   screen_width - 1, screen_height / 2));

   DFBCHECK (primary->Flip (primary, NULL, 0));
   sleep (5);
   primary->Release( primary );
   dfb->Release( dfb );
   return 23;
}

如您所见，我用硬编码char*提供参数。这是因为我计划从没有从命令行启动的代码中使用DirectFB。代码用命令gcc -i/usr/local/include/directfbdfbtest.c -o dfbtest -ldirectfb编译。

这会产生一个错误：

   ~~~~~~~~~~~~~~~~~~~~~~~~~~| DirectFB 1.2.10 |~~~~~~~~~~~~~~~~~~~~~~~~~~
    (c) 2001-2008  The world wide DirectFB Open Source Community
    (c) 2000-2004  Convergence (integrated media) GmbH
  ----------------------------------------------------------------

(*) DirectFB/ Core :单一应用程序核心。(2012-05-21 06:43)

(*)直接/线程:启动'VT开关‘(3285)关键其他/其他0/0 <8388608>。

(*)直接/模块:抑制模块“操纵杆”

(*)直接/模块:抑制模块‘键盘’