In OS X 10.4.9, Ruby 1.8.4 when I use:
Dir.mkdir(file_name, 755)

The directories created are drop-box, owner-only.
It seems the Dir class expects the leading bit.
So, it should be 0755 and not 755.

When using:
Dir.mkdir(file_name)

Without permissions, it appears to default to 0755.

Just thought this might be useful for some people.
Seems like I read this in the Pickaxe, but I forgot.
It is interesting, since chmod accepts 755 and assumes you mean 0755
Seems to me that Dir should do the same assuming... but doesn't


John Joyce