| Input Parameters | Significance |
| DtvLong idm | mask Id |
| Output Parameters | Significance |
| no | - |
| Return Code | Significance |
| 0 | no error |
| 1 | mask was already invisible |
Only use this function for request- or input masks, which have no reference to the data base. All masks that are carried by a widget and point to data base tables should only be removed using the function dal_wdg_del_wdg.