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Diffstat (limited to 'Documentation/DocBook/v4l/func-write.xml')
| -rw-r--r-- | Documentation/DocBook/v4l/func-write.xml | 136 |
1 files changed, 0 insertions, 136 deletions
diff --git a/Documentation/DocBook/v4l/func-write.xml b/Documentation/DocBook/v4l/func-write.xml deleted file mode 100644 index 2c09c09371c3..000000000000 --- a/Documentation/DocBook/v4l/func-write.xml +++ /dev/null @@ -1,136 +0,0 @@ -<refentry id="func-write"> - <refmeta> - <refentrytitle>V4L2 write()</refentrytitle> - &manvol; - </refmeta> - - <refnamediv> - <refname>v4l2-write</refname> - <refpurpose>Write to a V4L2 device</refpurpose> - </refnamediv> - - <refsynopsisdiv> - <funcsynopsis> - <funcsynopsisinfo>#include <unistd.h></funcsynopsisinfo> - <funcprototype> - <funcdef>ssize_t <function>write</function></funcdef> - <paramdef>int <parameter>fd</parameter></paramdef> - <paramdef>void *<parameter>buf</parameter></paramdef> - <paramdef>size_t <parameter>count</parameter></paramdef> - </funcprototype> - </funcsynopsis> - </refsynopsisdiv> - - <refsect1> - <title>Arguments</title> - - <variablelist> - <varlistentry> - <term><parameter>fd</parameter></term> - <listitem> - <para>&fd;</para> - </listitem> - </varlistentry> - <varlistentry> - <term><parameter>buf</parameter></term> - <listitem> - <para></para> - </listitem> - </varlistentry> - <varlistentry> - <term><parameter>count</parameter></term> - <listitem> - <para></para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> - - <refsect1> - <title>Description</title> - - <para><function>write()</function> writes up to -<parameter>count</parameter> bytes to the device referenced by the -file descriptor <parameter>fd</parameter> from the buffer starting at -<parameter>buf</parameter>. When the hardware outputs are not active -yet, this function enables them. When <parameter>count</parameter> is -zero, <function>write()</function> returns -<returnvalue>0</returnvalue> without any other effect.</para> - - <para>When the application does not provide more data in time, the -previous video frame, raw VBI image, sliced VPS or WSS data is -displayed again. Sliced Teletext or Closed Caption data is not -repeated, the driver inserts a blank line instead.</para> - </refsect1> - - <refsect1> - <title>Return Value</title> - - <para>On success, the number of bytes written are returned. Zero -indicates nothing was written. On error, <returnvalue>-1</returnvalue> -is returned, and the <varname>errno</varname> variable is set -appropriately. In this case the next write will start at the beginning -of a new frame. Possible error codes are:</para> - - <variablelist> - <varlistentry> - <term><errorcode>EAGAIN</errorcode></term> - <listitem> - <para>Non-blocking I/O has been selected using the <link -linkend="func-open"><constant>O_NONBLOCK</constant></link> flag and no -buffer space was available to write the data immediately.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><errorcode>EBADF</errorcode></term> - <listitem> - <para><parameter>fd</parameter> is not a valid file -descriptor or is not open for writing.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><errorcode>EBUSY</errorcode></term> - <listitem> - <para>The driver does not support multiple write streams and the -device is already in use.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><errorcode>EFAULT</errorcode></term> - <listitem> - <para><parameter>buf</parameter> references an inaccessible -memory area.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><errorcode>EINTR</errorcode></term> - <listitem> - <para>The call was interrupted by a signal before any -data was written.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><errorcode>EIO</errorcode></term> - <listitem> - <para>I/O error. This indicates some hardware problem.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><errorcode>EINVAL</errorcode></term> - <listitem> - <para>The <function>write()</function> function is not -supported by this driver, not on this device, or generally not on this -type of device.</para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> -</refentry> - -<!-- -Local Variables: -mode: sgml -sgml-parent-document: "v4l2.sgml" -indent-tabs-mode: nil -End: ---> |