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     40 >Video for Linux Two API Specification: Revision 0.24</TH
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     73 NAME="VIDIOC-LOG-STATUS"
     74 ></A
     75 >ioctl VIDIOC_LOG_STATUS</H1
     76 ><DIV
     77 CLASS="REFNAMEDIV"
     78 ><A
     79 NAME="AEN12788"
     80 ></A
     81 ><H2
     82 >Name</H2
     83 >VIDIOC_LOG_STATUS&nbsp;--&nbsp;Log driver status information</DIV
     84 ><DIV
     85 CLASS="REFSYNOPSISDIV"
     86 ><A
     87 NAME="AEN12791"
     88 ></A
     89 ><H2
     90 >Synopsis</H2
     91 ><DIV
     92 CLASS="FUNCSYNOPSIS"
     93 ><P
     94 ></P
     95 ><A
     96 NAME="AEN12792"
     97 ></A
     98 ><P
     99 ><CODE
    100 ><CODE
    101 CLASS="FUNCDEF"
    102 >int ioctl</CODE
    103 >(int fd, int request);</CODE
    104 ></P
    105 ><P
    106 ></P
    107 ></DIV
    108 ></DIV
    109 ><DIV
    110 CLASS="REFSECT1"
    111 ><A
    112 NAME="AEN12800"
    113 ></A
    114 ><H2
    115 >Description</H2
    116 ><P
    117 >As the video/audio devices become more complicated it
    118 becomes harder to debug problems. When this ioctl is called the driver
    119 will output the current device status to the kernel log. This is
    120 particular useful when dealing with problems like no sound, no video
    121 and incorrectly tuned channels. Also many modern devices autodetect
    122 video and audio standards and this ioctl will report what the device
    123 thinks what the standard is. Mismatches may give an indication where
    124 the problem is.</P
    125 ><P
    126 >This ioctl is optional and not all drivers support it. It
    127 was introduced in Linux 2.6.15.</P
    128 ></DIV
    129 ><DIV
    130 CLASS="REFSECT1"
    131 ><A
    132 NAME="AEN12804"
    133 ></A
    134 ><H2
    135 >Return Value</H2
    136 ><P
    137 >On success <SPAN
    138 CLASS="RETURNVALUE"
    139 >0</SPAN
    140 > is returned, on error <SPAN
    141 CLASS="RETURNVALUE"
    142 >-1</SPAN
    143 > and the <CODE
    144 CLASS="VARNAME"
    145 >errno</CODE
    146 > variable is set appropriately:</P
    147 ><P
    148 ></P
    149 ><DIV
    150 CLASS="VARIABLELIST"
    151 ><DL
    152 ><DT
    153 ><SPAN
    154 CLASS="ERRORCODE"
    155 >EINVAL</SPAN
    156 ></DT
    157 ><DD
    158 ><P
    159 >The driver does not support this ioctl.</P
    160 ></DD
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