The complete error message is:
gamsinst version 036 ==================== Installation of GAMS distribution 22.5 Continue? (Y/N) y Unpacking GAMS ... estimated disk blocks needed : 20480, available : 6841179 executing--> ./gamsunpack sh: ./gamsunpack: not found Error running unpacking script ./gamsunpack Aborting... $
gamsinst requires the csh being installed.
After installing the tcsh package (it does not come as default in some Linux distributions , e.g under ubuntu use:
sudo apt-get install tcsh) the problem was fixed.