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11 "NVIDIA Accelerated FreeBSD Graphics Driver README and Installation Guide">
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13 "Appendix K. VDPAU Support">
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39 <h2 class="title" style="clear: both"><a name="id2654584" id=
40 "id2654584"></a>Debugging and Tracing</h2>
44 <p>The VDPAU wrapper library supports tracing VDPAU function calls,
45 and their parameters. This tracing is controlled by the following
46 environment variables:</p>
47 <div class="variablelist">
49 <dt><span class="term">VDPAU_TRACE</span></dt>
51 <p>Enables tracing. Set to 1 to trace function calls. Set to 2 to
52 trace all arguments passed to the function.</p>
54 <dt><span class="term">VDPAU_TRACE_FILE</span></dt>
56 <p>Filename to write traces to. By default, traces are sent to
57 stderr. This variable may either contain a plain filename, or a
58 reference to an existing open file-descriptor in the format
59 "&N" where N is the file descriptor number.</p>
64 <p>The VDPAU wrapper library is responsible for determining which
65 vendor-specific driver to load for a given X11 display/screen. At
66 present, it hard-codes "nvidia" as the driver. The environment
67 variable VDPAU_DRIVER may be set to override this default. The
68 actual library loaded will be libvdpau_${VDPAU_DRIVER}.so. Setting
69 VDPAU_DRIVER to "trace" is not advised.</p>
70 <p>The NVIDIA VDPAU driver can emit some diagnostic information
71 when an error occurs. To enable this, set the environment variable
72 VDPAU_NVIDIA_DEBUG. A value of 1 will request a small diagnostic
73 that will enable NVIDIA engineers to locate the source of the
74 problem. A value of 3 will request that a complete stack backtrace
75 be printed, which provide NVIDIA engineers with more detailed
76 information, which may be needed to diagnose some problems.</p>
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95 Appendix L. Tips for New FreeBSD Users</td>