GtkTextView issue through struct

typedef struct _GtkPassedServerSwitchData {
    GtkWidget *text;
    GtkWidget *window;
} GtkPassedServerSwitchData;

static void
switch_pos_cb (GtkSwitch *sw, gpointer user_data)
{
    GPid pid;
    gboolean check;
    gboolean check_pid;
    FILE *get_pid;
    gchar pid_string[16];
    GtkWidget *window;
        GtkPassedServerSwitchData *rdata;

    check = gtk_switch_get_active (sw);
    pid = -2;
    rdata = user_data;


        gtk_text_view_set_editable (GTK_TEXT_VIEW (rdata -> text), FALSE);
        gtk_text_view_set_cursor_visible (GTK_TEXT_VIEW (rdata -> text), TRUE);

    /* Here we get the `GPid pid` from the `get_pid` statement, which
    uses the `pgrep` command to obtain the pid, and convert it to a gint
    using the `g_ascii_strtoll ()` function. */
    get_pid = popen ("pgrep jackd", "r");

    while (fgets (pid_string, sizeof (pid_string), get_pid) != NULL)
    {
        pid = atoi (pid_string);
    }

    pclose (get_pid);

    /* Check if `GPid pid` exists. */
    check_pid = kill (pid, 0);

    if (check == TRUE)
    {
        gtk_widget_set_tooltip_text (GTK_WIDGET (sw) , "Shutdown Server");

        /* If server isn't started yet, start it here when switch is
        turned on. */
        if (check_pid != 0)
        {
            //jack_server_init (sw, pid, rdata -> text, rdata -> window);
        }
    }
    else
    {
        gtk_widget_set_tooltip_text (GTK_WIDGET (sw) , "Start Server");
        kill (pid, SIGTERM);
    }
}

void
server_switch (GtkWidget *window,
               GtkWidget *text,
               GtkApplication *app,
               GtkWidget *header_bar)
{
    GtkWidget *jack_switch;
    gchar result[10];
    gint check_pid;
    gboolean check;
    FILE *cmd;
    GPid pid;
        GtkPassedServerSwitchData *pdata;

    pid = -2;
    cmd = popen ("pgrep jackd", "r");
    jack_switch = gtk_switch_new ();
    check = gtk_switch_get_active (GTK_SWITCH (jack_switch));

        //pdata = (GtkPassedServerSwitchData *) g_malloc (sizeof (GtkPassedServerSwitchData));
        pdata = g_slice_new0 (GtkPassedServerSwitchData);
        pdata -> window = window;
        pdata -> text = text;

    /* Here we get the `GPid pid` from the `cmd` statement and convert
    it to a gint using the `g_ascii_strtoll ()` function. */
    while (fgets (result, sizeof (result), cmd) != NULL)
    {
        pid = g_ascii_strtoll (result, NULL, 10);
    }

    pclose (cmd);

    /* Check to see if server is already started. If it is we call
    `dsp_init ()` to create this program as a JACK client and obtain
    cpu load. */
    check_pid = kill (pid, 0);
    if (check_pid == 0)
    {
        dsp_init (jack_switch, pid);
    }

    gtk_header_bar_pack_start (GTK_HEADER_BAR (header_bar), jack_switch);

    gtk_widget_set_valign (jack_switch, GTK_ALIGN_CENTER);

    gjackctl_settings (window, app, header_bar);
    //connections (vbox);



    /* Initiate tooltip for `jack_switch` here or else it won't show when
    app first starts. */
    if (check == TRUE)
    {
        gtk_widget_set_tooltip_text (GTK_WIDGET (jack_switch),
                                     "Shutdown Server");
    }
    else
    {
        gtk_widget_set_tooltip_text (GTK_WIDGET (jack_switch),
                                     "Start Server");
    }

    g_signal_connect (jack_switch,
                      "notify::active",
                      G_CALLBACK (switch_pos_cb),
                      pdata);
}