If the user is passing in the * on the command line, then what you have would work if you switched over to glob.

Assuming it was quoted. If it wasn't quoted, and one isn't using the Windows command shell, the shell would have done the globbing itself.

$ perl -E'say for @ARGV' 'tmp/*'
tmp/*

$ perl -E'say for @ARGV' tmp/*
tmp/a
tmp/b
tmp/c
tmp/d
tmp/e
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