The alias name will hide other layers if there is a name clash. This can be used for layer remapping, but the user must be careful with this. Layer name comparisons are case-insensitive.
Unlike the normal layer names, the alias name can have arbitrary punctuation, embedded white space, etc. However, leading and trailing white space is removed, and if the resulting string is empty or null, the existing alias name (if any) will be removed.
The function returns 1 if the alias name is applied to the layer, 0 if an error occurs. It is not possible to set the same name on more than one layer.
The function returns 1 on success, or 0 if the layer number or data type number is out of range. The acceptable range for the layer number and data type is [0 - 65535].
The return value is -1 if the layer number or data type is out of range. Otherwise, the return value is the number of mappings removed.
The function returns 0 if there was a syntax error. The function returns 1 if the mapping is successfully added.