I've used the snap package manager to install packages and I'm always getting the same error, even with the simple hello world example:

$ sudo snap install hello
$ hello
cannot create user data directory: /home/aaa/snap/hello/20: Bad file descriptor

Running with sudo solves the problem for the hello program, but why do I even need to do sudo?

BTW, for the other packages (Meshlab, CloudCompare) it doesn't work also with sudo and gives different errors. For example:

~$ sudo cloudcompare.ccViewer 
mkdir: cannot create directory '/run/user/0': Permission denied
No protocol specified
QXcbConnection: Could not connect to display :0

The snap version and Ubuntu distro are:

$ snap version
snap    2.22.7
snapd   2.22.7
series  16
ubuntu  14.04
kernel  4.4.0-64-generic