How do I organize files by creation date?

Question

How would I sort a directory into files created before and after any given time and date?

I need to make two lists, one of files before, and the other of files after, a certain date/time.

Answer 1

The creation time with Ruby on OS X is not available through the File API. One way is shelling out to stat(1). Not pretty but does at least return the creation (a.k.a birth) time:

def birth(file)
  Time.at(`stat -f%B "#{file}"`.chomp.to_i)
end

Dir.entries('.').sort_by {|f| birth f }

Or use the partition answer given.

Here's a detailed post on a common misconception: ctime does not mean creation time.

Answer 2

Dir["dir_path/*"].sort_by { |p| File::Stat.new(p).birthtime } works on macos

Answer 3

You can use Enumerable#partition:

files = Dir.entries('.')
time = Time.parse("2013-09-01")
before, after = files.partition { |file| File.ctime(file) < time }

As the Tin Man noted, ctime is not the only file time method. Maybe atime or mtime is a better choice.

Answer 4

ctime

Returns the change time for stat (that is, the time directory information about the file was changed, not the file itself).

Note that on Windows (NTFS), returns creation time (birth time).

http://www.ruby-doc.org/core-2.0.0/File/Stat.html#method-i-ctime

so you can do something like this.

Dir.entries('.').sort {|a,b| File.stat(a).ctime <=> File.stat(b).ctime}

Answer 5

Here's my answer. You can sort the files in a directory by their modified time with something along these lines using File.new('filename').mtime

files_hash = Hash.new

Dir.foreach('.') do |file_name|
  modified_time = File.new(file_name).mtime
  unless file_name == '.' || file_name == '..' then
    files_hash[file_name] = modified_time
  end
end

# Sort the hash.
files_hash = files_hash.sort_by {|key, value| value}

files_hash.each do |name, time|
  puts "#{name} was modified at #{time}"
end