How to delete read-only files with Ruby commands

ruby-talk
1

All-

On a Windows NT system, is there a way to quickly delete directories (from within a Ruby script) that may have read-only files in them. The command I’ve been using is

File.delete(Dir[".*"])

but this crashes when it hits a RO file.

Similarly, is there a way to force the overwriting of a RO file? I’ve been using File.syscopy, but this, too, crashes when attempting to overwrite an RO file.

Thanks!

-Kurt Euler

2

Kurt Euler wrote:

All-

On a Windows NT system, is there a way to quickly delete directories (from within a Ruby script) that may have read-only files in them. The command I’ve been using is

File.delete(Dir[".*"])

but this crashes when it hits a RO file.

Similarly, is there a way to force the overwriting of a RO file? I’ve been using File.syscopy, but this, too, crashes when attempting to overwrite an RO file.

I’d suggest this: Get a list of files first and iterate over it.
Wrap in a begin/end and catch the exception. When you get the
exception for a RO file, explicitly change it to be writable
and do a retry.

Something like:

files = Dir[“.”]
files.each do |file|
begin
File.delete(file)
rescue Whatever
system(“whatever #{file}”)
retry
end
end

I don’t know the exception or how to fix it in Windoze. Any other
mistakes I made are due to the lateness of the hour.

Hal

3

All-

On a Windows NT system, is there a way to quickly delete directories
(from within a Ruby script) that may have read-only files in them. The
command I’ve been using is

File.delete(Dir[".*"])

but this crashes when it hits a RO file.

Similarly, is there a way to force the overwriting of a RO file? I’ve
been using File.syscopy, but this, too, crashes when attempting to
overwrite an RO file.

Thanks!

-Kurt Euler

Try the standard library file ‘fileutils.rb’. You can RDoc the file to
see some documentation or (of course) look at the file directly.

From memory:

require ‘fileutils’

FileUtils.rm_rf(directory) # trash a directory tree
FileUtils.cp(src, dest, :force => true) # copy over a RO file

These use Unix names, but I imagine it will work on Windows.

Gavin

4

Gavin Sinclair wrote:

require ‘fileutils’

FileUtils.rm_rf(directory) # trash a directory tree
FileUtils.cp(src, dest, :force => true) # copy over a RO file

These use Unix names, but I imagine it will work on Windows.

Looks like it will (remove_file is ultimately called by rm_rf and
variants…)

  def remove_file( fname, force = false ) #:nodoc:
    first_time_p = true
    begin
      File.unlink fname
    rescue Errno::ENOENT
      raise unless force
    rescue
      if first_time_p
        # try once more for Windows
        first_time_p = false
        File.chmod 0777, fname
        retry
      end
      raise
    end
  end

A slightly more direct version, which I know is good for Windows, but
not verified on *nix[1]:

    files.each do |file|
      # make writable to allow deletion
      File.chmod(0644, file)
      File.delete(file)
    end

[1] from http://www.clabs.org/dl/clutil/

···

–

Chris
http://clabs.org/blogki