<?xml version="1.0" encoding="ANSI_X3.4-1968" standalone="no"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968" /><title>CA Function Calls</title><meta name="generator" content="DocBook XSL Stylesheets V1.75.2" /><link rel="home" href="index.html" title="LINUX MEDIA INFRASTRUCTURE API" /><link rel="up" href="ch13.html" title="Chapter 13. DVB CA Device" /><link rel="prev" href="ch13.html" title="Chapter 13. DVB CA Device" /><link rel="next" href="ch14.html" title="Chapter 14. DVB Network API" /></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">CA Function Calls</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ch13.html">Prev</a> </td><th width="60%" align="center">Chapter 13. DVB CA Device</th><td width="20%" align="right"> <a accesskey="n" href="ch14.html">Next</a></td></tr></table><hr /></div><div class="section" title="CA Function Calls"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="ca_function_calls"></a>CA Function Calls</h2></div></div></div><div class="toc"><dl><dt><span class="section"><a href="ch13s02.html#ca_fopen">open()</a></span></dt><dt><span class="section"><a href="ch13s02.html#ca_fclose">close()</a></span></dt></dl></div><div class="section" title="open()"><div class="titlepage"><div><div><h3 class="title"><a id="ca_fopen"></a>open()</h3></div></div></div><p>DESCRIPTION </p><div class="informaltable"><table border="1"><colgroup><col /></colgroup><tbody><tr><td align="char"> <p>This system call opens a named ca device (e.g. /dev/ost/ca) for subsequent use.</p> <p>When an open() call has succeeded, the device will be ready for use. The significance of blocking or non-blocking mode is described in the documentation for functions where there is a difference. It does not affect the semantics of the open() call itself. A device opened in blocking mode can later be put into non-blocking mode (and vice versa) using the F_SETFL command of the fcntl system call. This is a standard system call, documented in the Linux manual page for fcntl. Only one user can open the CA Device in O_RDWR mode. All other attempts to open the device in this mode will fail, and an error code will be returned.</p> </td></tr></tbody></table></div><p>SYNOPSIS </p><div class="informaltable"><table border="1"><colgroup><col /></colgroup><tbody><tr><td align="char"> <p>int open(const char ⋆deviceName, int flags);</p> </td></tr></tbody></table></div><p>PARAMETERS </p><div class="informaltable"><table border="1"><colgroup><col /><col /></colgroup><tbody><tr><td align="char"> <p>const char *deviceName</p> </td><td align="char"> <p>Name of specific video device.</p> </td></tr><tr><td align="char"> <p>int flags</p> </td><td align="char"> <p>A bit-wise OR of the following flags:</p> </td></tr><tr><td align="char"> </td><td align="char"> <p>O_RDONLY read-only access</p> </td></tr><tr><td align="char"> </td><td align="char"> <p>O_RDWR read/write access</p> </td></tr><tr><td align="char"> </td><td align="char"> <p>O_NONBLOCK open in non-blocking mode</p> </td></tr><tr><td align="char"> </td><td align="char"> <p>(blocking mode is the default)</p> </td></tr></tbody></table></div><p>ERRORS </p><div class="informaltable"><table border="1"><colgroup><col /><col /></colgroup><tbody><tr><td align="char"> <p>ENODEV</p> </td><td align="char"> <p>Device driver not loaded/available.</p> </td></tr><tr><td align="char"> <p>EINTERNAL</p> </td><td align="char"> <p>Internal error.</p> </td></tr><tr><td align="char"> <p>EBUSY</p> </td><td align="char"> <p>Device or resource busy.</p> </td></tr><tr><td align="char"> <p>EINVAL</p> </td><td align="char"> <p>Invalid argument.</p> </td></tr></tbody></table></div></div><div class="section" title="close()"><div class="titlepage"><div><div><h3 class="title"><a id="ca_fclose"></a>close()</h3></div></div></div><p>DESCRIPTION </p><div class="informaltable"><table border="1"><colgroup><col /></colgroup><tbody><tr><td align="char"> <p>This system call closes a previously opened audio device.</p> </td></tr></tbody></table></div><p>SYNOPSIS </p><div class="informaltable"><table border="1"><colgroup><col /></colgroup><tbody><tr><td align="char"> <p>int close(int fd);</p> </td></tr></tbody></table></div><p>PARAMETERS </p><div class="informaltable"><table border="1"><colgroup><col /><col /></colgroup><tbody><tr><td align="char"> <p>int fd</p> </td><td align="char"> <p>File descriptor returned by a previous call to open().</p> </td></tr></tbody></table></div><p>ERRORS </p><div class="informaltable"><table border="1"><colgroup><col /><col /></colgroup><tbody><tr><td align="char"> <p>EBADF</p> </td><td align="char"> <p>fd is not a valid open file descriptor.</p> </td></tr></tbody></table></div></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="ch13.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="ch13.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="ch14.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter 13. DVB CA Device </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> Chapter 14. DVB Network API</td></tr></table></div></body></html>
