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>4.2. The GOption interface</A
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> You can also use a GOption table to initialize your own parameters as
shown in the next example:
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>Example 4-2. Initialisation using the GOption interface</B
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>
#include <gst/gst.h>
int
main (int argc,
char *argv[])
{
gboolean silent = FALSE;
gchar *savefile = NULL;
GOptionContext *ctx;
GError *err = NULL;
GOptionEntry entries[] = {
{ "silent", 's', 0, G_OPTION_ARG_NONE, &silent,
"do not output status information", NULL },
{ "output", 'o', 0, G_OPTION_ARG_STRING, &savefile,
"save xml representation of pipeline to FILE and exit", "FILE" },
{ NULL }
};
/* we must initialise the threading system before using any
* other GLib funtion, such as g_option_context_new() */
if (!g_thread_supported ())
g_thread_init (NULL);
ctx = g_option_context_new ("- Your application");
g_option_context_add_main_entries (ctx, entries, NULL);
g_option_context_add_group (ctx, gst_init_get_option_group ());
if (!g_option_context_parse (ctx, &argc, &argv, &err)) {
g_print ("Failed to initialize: %s\n", err->message);
g_error_free (err);
return 1;
}
printf ("Run me with --help to see the Application options appended.\n");
return 0;
}
</PRE
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> As shown in this fragment, you can use a <A
HREF="http://developer.gnome.org/doc/API/2.0/glib/glib-Commandline-option-parser.html"
TARGET="_top"
>GOption</A
> table to define your application-specific
command line options, and pass this table to the GLib initialization
function along with the option group returned from the
function <CODE
CLASS="function"
>gst_init_get_option_group</CODE
>. Your
application options will be parsed in addition to the standard
<SPAN
CLASS="application"
>GStreamer</SPAN
> options.
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