On Sophos Anti-Virus for Linux, using the wildcard '*' with the ExcludeFileOnGlob savconfig option, will cause all of the excluded files to be listed.
This is as expected for a Linux command. The Linux shell expands '*' before passing the arguments to savconfig.
For example, running:
/opt/sophos-av/bin/savconfig ExcludeOnGlob /tmp/virus/*
will cause all of the excluded files in the directory /tmp/virus to be listed.