# regex matching an acceptable filename in "this" directory
# must begin with an alphanumeric character
-# and contain only alphanumeric, underscore, plus sign, hyphen, dot, and tilde
+# and contain only hyphen, dot, alphanumeric, underscore, plus sign, and tilde
# note that an acceptable filename may not begin with dot, so ".." is out
my $RE_filename_here = qr/[[:alnum:]][-.[:alnum:]_+~]*/;
# regex matching an acceptable relative filename in POSIX syntax