Ruby Programming/Reference/Objects/IO/File

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The file class is typically used for opening and closing files, as well as a few methods like deleting them and stat'ing them.

If you want to manipulate a file, not open it, also check out the Pathname class, as well as the FileUtils class.

To create a directory you'll need to use the Dir.mkdir method.


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Here's how to do the equivalent of "chmod u+x filename"

File.class_eval do
   def self.addmod(flags, filename)
     themode=stat(filename).mode | flags
     chmod(themode, filename)

Although there's no error checking and the return value could probably be something better (like themode).

So after defining that, your 'u+w' would be: @File.addmod(0200, 'filename')@ from


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This is actually Enumerable#grep, and I believe it just works piece-wise, like File.each_line{|l|yield l if l=~ /whatever/ }


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This is useful for combining objects that aren't (or might not be) strings into a path. See here.