problem using pkg install : "Package is missing file: COPYING"

[Timothée Brochier]

hello,
I want to install the netcdf package for octave (with octave 2.9.9 on  
an intel mac). Here is what I get :

octave:2> pkg install /Users/timbrochier/Desktop/Telechargements/ 
octave-intel-bin.tar
error: Package is missing file: COPYING
octave:2>

If anyone can help me fixing that, o tell me another way to install  
the package...

Thank you very much,

Timothee