The number of pages that will be printed. Note that this value is set during print preparation phase (%GTK_PRINT_STATUS_PREPARING), so this value should never be get before the data generation phase (%GTK_PRINT_STATUS_GENERATING_DATA). You can connect to the GtkPrintOperation::status-changed signal and call gtk_print_operation_get_n_pages_to_print() when print status is %GTK_PRINT_STATUS_GENERATING_DATA. This is typically used to track the progress of print operation.