Bug on Ubuntu 19.04 about xsuspender HOT 5 CLOSED

static
gboolean
is_on_ac_power ()
{
#ifdef __linux__
    // Read AC power state from /sys/class/power_supply/AC/online (== 1 on AC).
    // Should work in most cases. See: https://bugs.debian.org/473629

    const char *DIRNAME = "/sys/class/power_supply/AC";
    g_autoptr (GError) err = NULL;

	g_autofree char *filename = g_build_filename (DIRNAME, "online", NULL);
	g_autofree char *contents = NULL;

	g_debug ("Reading '%s'", filename);
	if (! g_file_get_contents (filename, &contents, NULL, &err)) {
	    g_debug ("Cannot read '%s': %s", filename, err->message);
	}

	if (g_strcmp0 (g_strstrip (contents), "1") == 0)
	    return TRUE;
    
    #warning "No battery / AC status support for your platform."
    #warning "Defaulting to as if 'always on battery' behavior. Patches welcome!"
    return FALSE;

#elif defined(__unix__) && defined(BSD) && !defined(__APPLE__)
    // On *BSD, run `apm -a` which returns '1' when AC is online
    g_autoptr (GError) err = NULL;
    g_autofree char *standard_output = NULL;
    char *argv[] = {"apm", "-a", NULL};

    g_spawn_sync (NULL, argv, NULL, G_SPAWN_SEARCH_PATH | G_SPAWN_STDERR_TO_DEV_NULL,
                  NULL, NULL, &standard_output, NULL, NULL, &err);
    if (err)
        g_warning ("Unexpected `apm -a` execution error: %s", err->message);

    return standard_output && 0 == g_strcmp0 (g_strstrip (standard_output), "1");
#endif
}