You want to set $mode to the octal 0755 which is quite different from the string "0755" e.g

## incorrect
shell> perl -e 'mkdir "foo", "0755"' && ls -ld foo
d-wxr----t    2 perl      monks          1024 May 28 14:50 foo
shell> rmdir foo
## correct
shell> perl -e 'mkdir "foo", 0755' && ls -ld foo
drwxr-xr-x    2 perl      monks          1024 May 28 14:50 foo
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HTH

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broquaint