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Methods

A

Class Public methods

atomic_write(file_name, temp_dir = dirname(file_name))Link

Write to a file atomically. Useful for situations where you don’t want other processes or threads to see half-written files.

File.atomic_write('important.file') do |file|
  file.write('hello')
end

This method needs to create a temporary file. By default it will create it in the same directory as the destination file. If you don’t like this behavior you can provide a different directory but it must be on the same physical filesystem as the file you’re trying to write.

File.atomic_write('/data/something.important', '/data/tmp') do |file|
  file.write('hello')
end

Source: show | on GitHub

def self.atomic_write(file_name, temp_dir = dirname(file_name)) require "tempfile" unless defined?(Tempfile)

Tempfile.open(".#{basename(file_name)}", temp_dir) do |temp_file| temp_file.binmode return_val = yield temp_file temp_file.close

old_stat = if exist?(file_name)
  
  stat(file_name)
else
  
  
  probe_stat_in(dirname(file_name))
end

if old_stat
  
  begin
    chown(old_stat.uid, old_stat.gid, temp_file.path)
    
    chmod(old_stat.mode, temp_file.path)
  rescue Errno::EPERM, Errno::EACCES
    
  end
end


rename(temp_file.path, file_name)
return_val

end end