$ ls -1 /tmp/test/
other.txt
test10.txt
test1.txt
test2.txt
test3.txt

##</code><code>##

$ perl find_files.pl test*.txt

##</code><code>##

$ perl find_files.pl 'test.*\.txt'
wildcard is test.*\.txt
/tmp/test/test10.txt
/tmp/test/test3.txt
/tmp/test/test2.txt
/tmp/test/test1.txt