$filename_a = "c:\\abc.log";
$filename_b = "c:\\abc.log";
$filename_b_re = qr/c:\\abc.log/;

print "Are they equal ? : ";
print $filename_a eq $filename_b ; # output is 1

print "\n";
print "Do they match ? : ";
print $filename_a =~ /$filename_b_re/ ; # output is 1