[Gmsh] Saving volume mesh in STL format

[Rémi Blandin]

Dear mister Geuzaine,

I use gmsh to generate 3D volume meshes and it works perfectly for that, 
but when I try to
export it to stl format only the surface elements are saved.

Why is it not possible to save the entire mesh under the stl format ?
Do you know a way to do it ?

Thank you in advance for you help,

Rémi Blandin