concat.rb

#!/usr/bin/env

# NOTE, Untested code.
#
# Possibly one of the faster wasy to concatenate two files in ruby.
# Another way might be to use the lower level IO#sysread, IO#syswrite methods
# I think the main benefit in this case is the reusing of the String instance as
# the buffer.

dest = ARGV.shift
src  = ARGV.shift

bufsize = File.stat( dest ).blksize || 8192

File.open( dest, "a" ) do |d|
  File.open( src, "r" ) do |r|
    buffer = String.new()
    while b = r.read( bufsize, buffer ) do
      w.write( b )
    end
  end
end