While GDL has CMSvlib installed to read / write IDL
.sav files, here is how to install CMSvlib if desired.
Download CMSVlib and extract to “~/.local/share/cmsvlib”. Add line to ~/.profile:
Copy and paste into “~/.gdl/gdl-startup.pro”
Reopen Terminal and GDL. Load IDL .sav file like:
Check GDL paths loaded: