+ * The main use for #GApplicationCommandLine (and the
+ * #GApplication::command-line signal) is 'Emacs server' like use cases:
+ * You can set the `EDITOR` environment variable to have e.g. git use
+ * your favourite editor to edit commit messages, and if you already
+ * have an instance of the editor running, the editing will happen
+ * in the running instance, instead of opening a new one. An important
+ * aspect of this use case is that the process that gets started by git
+ * does not return until the editing is done.
+ *
+ * Normally, the commandline is completely handled in the
+ * #GApplication::command-line handler. The launching instance exits
+ * once the signal handler in the primary instance has returned, and
+ * the return value of the signal handler becomes the exit status
+ * of the launching instance.
+ * |[<!-- language="C" -->
+ * static int
+ * command_line (GApplication *application,
+ * GApplicationCommandLine *cmdline)
+ * {
+ * gchar **argv;
+ * gint argc;
+ * gint i;
+ *
+ * argv = g_application_command_line_get_arguments (cmdline, &argc);
+ *
+ * g_application_command_line_print (cmdline,
+ * "This text is written back\n"
+ * "to stdout of the caller\n");
+ *
+ * for (i = 0; i < argc; i++)
+ * g_print ("argument %d: %s\n", i, argv[i]);
+ *
+ * g_strfreev (argv);
+ *
+ * return 0;
+ * }
+ * ]|
+ * The complete example can be found here:
+ * [gapplication-example-cmdline.c](https://git.gnome.org/browse/glib/tree/gio/tests/gapplication-example-cmdline.c)
+ *
+ * In more complicated cases, the handling of the comandline can be
+ * split between the launcher and the primary instance.
+ * |[<!-- language="C" -->
+ * static gboolean
+ * test_local_cmdline (GApplication *application,
+ * gchar ***arguments,
+ * gint *exit_status)
+ * {
+ * gint i, j;
+ * gchar **argv;
+ *
+ * argv = *arguments;
+ *
+ * i = 1;
+ * while (argv[i])
+ * {
+ * if (g_str_has_prefix (argv[i], "--local-"))
+ * {
+ * g_print ("handling argument %s locally\n", argv[i]);
+ * g_free (argv[i]);
+ * for (j = i; argv[j]; j++)
+ * argv[j] = argv[j + 1];
+ * }
+ * else
+ * {
+ * g_print ("not handling argument %s locally\n", argv[i]);
+ * i++;
+ * }
+ * }
+ *
+ * *exit_status = 0;
+ *
+ * return FALSE;
+ * }
+ *
+ * static void
+ * test_application_class_init (TestApplicationClass *class)
+ * {
+ * G_APPLICATION_CLASS (class)->local_command_line = test_local_cmdline;
+ *
+ * ...
+ * }
+ * ]|
+ * In this example of split commandline handling, options that start
+ * with `--local-` are handled locally, all other options are passed
+ * to the #GApplication::command-line handler which runs in the primary
+ * instance.
+ *
+ * The complete example can be found here:
+ * [gapplication-example-cmdline2.c](https://git.gnome.org/browse/glib/tree/gio/tests/gapplication-example-cmdline2.c)
+ *
+ * If handling the commandline requires a lot of work, it may
+ * be better to defer it.
+ * |[<!-- language="C" -->
+ * static gboolean
+ * my_cmdline_handler (gpointer data)
+ * {
+ * GApplicationCommandLine *cmdline = data;
+ *
+ * // do the heavy lifting in an idle
+ *
+ * g_application_command_line_set_exit_status (cmdline, 0);
+ * g_object_unref (cmdline); // this releases the application
+ *
+ * return G_SOURCE_REMOVE;
+ * }
+ *
+ * static int
+ * command_line (GApplication *application,
+ * GApplicationCommandLine *cmdline)
+ * {
+ * // keep the application running until we are done with this commandline
+ * g_application_hold (application);
+ *
+ * g_object_set_data_full (G_OBJECT (cmdline),
+ * "application", application,
+ * (GDestroyNotify)g_application_release);
+ *
+ * g_object_ref (cmdline);
+ * g_idle_add (my_cmdline_handler, cmdline);
+ *
+ * return 0;
+ * }
+ * ]|
+ * In this example the commandline is not completely handled before
+ * the #GApplication::command-line handler returns. Instead, we keep
+ * a reference to the #GApplicationCommandLine object and handle it
+ * later (in this example, in an idle). Note that it is necessary to
+ * hold the application until you are done with the commandline.
+ *
+ * The complete example can be found here:
+ * [gapplication-example-cmdline3.c](https://git.gnome.org/browse/glib/tree/gio/tests/gapplication-example-cmdline3.c)
+ */