[media] DocBook/frontend.xml: Recomend the usage of the new API

The old way of setting delivery system parameters were to use
an union with specific per-system parameters. However, as newer
delivery systems required more data, the structure size weren't
enough to fit. So, recomend using the DVBS2API instead.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Mauro Carvalho Chehab 2011-06-07 20:43:25 -03:00
Родитель 17d8bb061f
Коммит df2692a6dd
1 изменённых файлов: 14 добавлений и 2 удалений

Просмотреть файл

@ -221,8 +221,20 @@ by</para>
<section id="dvb-frontend-parameters">
<title>frontend parameters</title>
<para>The kind of parameters passed to the frontend device for tuning depend on
the kind of hardware you are using. All kinds of parameters are combined as an
union in the FrontendParameters structure:</para>
the kind of hardware you are using.</para>
<para>The struct <constant>dvb_frontend_parameters</constant> uses an
union with specific per-system parameters. However, as newer delivery systems
required more data, the structure size weren't enough to fit, and just
extending its size would break the existing applications. So, those parameters
were replaced by the usage of <link linkend="FE_GET_SET_PROPERTY">
<constant>FE_GET_PROPERTY/FE_SET_PROPERTY</constant></link> ioctl's. The
new API is flexible enough to add new parameters to existing delivery systems,
and to add newer delivery systems.</para>
<para>So, newer applications should use <link linkend="FE_GET_SET_PROPERTY">
<constant>FE_GET_PROPERTY/FE_SET_PROPERTY</constant></link> instead, in
order to be able to support the newer System Delivery like DVB-S2, DVB-T2,
DVB-C2, ISDB, etc.</para>
<para>All kinds of parameters are combined as an union in the FrontendParameters structure:</para>
<programlisting>
struct dvb_frontend_parameters {
uint32_t frequency; /&#x22C6; (absolute) frequency in Hz for QAM/OFDM &#x22C6;/