If you used the strictures use strict;use warnings;, you would have seen these warning messages:

Unrecognized escape \D passed through
Unrecognized escape \M passed through
Unrecognized escape \s passed through
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Use single quotes to avoid interpolation:

my $filename_with_path_dos = 'C:\Documents and Settings\My Documents\s
+ample.txt';
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This prints:

path is /usr/local/sample.txt
TEST #1
sample
/usr/local/
.txt
File is sample.txt
TEST #2
path is C:\Documents and Settings\My Documents\sample.txt
C:\Documents and Settings\My Documents\sample.txt
./

File is C:\Documents and Settings\My Documents\sample.txt
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