Naming system (what does the system see?)

I am currently using the tex_name command to trace the name of three seperate terrain files as my player moves over them. However, I have noticed that, even if I save my terrain file as "terrainone", it shows up as "terrainone_hmp_000" inside of WED. In the case of tex_name, what does the engine see as the entity's name? The exact name I entered when I saved the file, or does it add the file type on the end (Ex: .mdl, .hmp, ect.)?

Regards,
Raddaddy

As the manual said in c_trace->scan_texture: The predefined string
tex_name is set to the texture name of the surface hit by the ray, or
the entity file name if a model, sprite, or terrain was hit.

It is the file name (xxxxxx.MDL), or you can check it in
WED->entity->properties->File.