95 lines
2.8 KiB
XML
95 lines
2.8 KiB
XML
<refentry id="media-func-open">
|
|
<refmeta>
|
|
<refentrytitle>media open()</refentrytitle>
|
|
&manvol;
|
|
</refmeta>
|
|
|
|
<refnamediv>
|
|
<refname>media-open</refname>
|
|
<refpurpose>Open a media device</refpurpose>
|
|
</refnamediv>
|
|
|
|
<refsynopsisdiv>
|
|
<funcsynopsis>
|
|
<funcsynopsisinfo>#include <fcntl.h></funcsynopsisinfo>
|
|
<funcprototype>
|
|
<funcdef>int <function>open</function></funcdef>
|
|
<paramdef>const char *<parameter>device_name</parameter></paramdef>
|
|
<paramdef>int <parameter>flags</parameter></paramdef>
|
|
</funcprototype>
|
|
</funcsynopsis>
|
|
</refsynopsisdiv>
|
|
|
|
<refsect1>
|
|
<title>Arguments</title>
|
|
|
|
<variablelist>
|
|
<varlistentry>
|
|
<term><parameter>device_name</parameter></term>
|
|
<listitem>
|
|
<para>Device to be opened.</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
<varlistentry>
|
|
<term><parameter>flags</parameter></term>
|
|
<listitem>
|
|
<para>Open flags. Access mode must be either <constant>O_RDONLY</constant>
|
|
or <constant>O_RDWR</constant>. Other flags have no effect.</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
</variablelist>
|
|
</refsect1>
|
|
<refsect1>
|
|
<title>Description</title>
|
|
<para>To open a media device applications call <function>open()</function>
|
|
with the desired device name. The function has no side effects; the device
|
|
configuration remain unchanged.</para>
|
|
<para>When the device is opened in read-only mode, attempts to modify its
|
|
configuration will result in an error, and <varname>errno</varname> will be
|
|
set to <errorcode>EBADF</errorcode>.</para>
|
|
</refsect1>
|
|
<refsect1>
|
|
<title>Return Value</title>
|
|
|
|
<para><function>open</function> returns the new file descriptor on success.
|
|
On error, -1 is returned, and <varname>errno</varname> is set appropriately.
|
|
Possible error codes are:</para>
|
|
|
|
<variablelist>
|
|
<varlistentry>
|
|
<term><errorcode>EACCES</errorcode></term>
|
|
<listitem>
|
|
<para>The requested access to the file is not allowed.</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
<varlistentry>
|
|
<term><errorcode>EMFILE</errorcode></term>
|
|
<listitem>
|
|
<para>The process already has the maximum number of files open.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
<varlistentry>
|
|
<term><errorcode>ENFILE</errorcode></term>
|
|
<listitem>
|
|
<para>The system limit on the total number of open files has been
|
|
reached.</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
<varlistentry>
|
|
<term><errorcode>ENOMEM</errorcode></term>
|
|
<listitem>
|
|
<para>Insufficient kernel memory was available.</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
<varlistentry>
|
|
<term><errorcode>ENXIO</errorcode></term>
|
|
<listitem>
|
|
<para>No device corresponding to this device special file exists.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
</variablelist>
|
|
</refsect1>
|
|
</refentry>
|