| Input Parameters | Significance |
| DtvLong *idm | Id of the mask |
| Output Parameters | Significance |
| DtvLong *idm | Id of the mask |
| Return Code | Significance |
| 0 | no error |
| 1 | no further mask exists |
This function allows you to navigate in the mask stack. As opposed to dal_mas_ret_nxt_mas nested calls are allowed and is recommended to be used for DataView version 3.0-07 and higher.
If a zero ID is passed for idm, the function will return the ID of the first mask in the stack.