def charset_alias(config_charset, mapfile, target = OS)
map = Hash::Ordered.new
comments = []
IO.foreach("|#{SHELL} #{config_charset} #{target}") do |list|
next comments << list if /^\#/ =~ list
next unless /^(\S+)\s+(\S+)$/ =~ list
sys, can = $1, $2
can.downcase!
map[can] = sys
end
case target
when /linux|-gnu/
map.delete('ascii')
when /cygwin/
map['shift_jis'] = 'cp932'
end
open(mapfile, "w") do |f|
f.puts("require 'iconv.so'")
f.puts
f.puts(comments)
f.puts("class Iconv")
map.each {|can, sys| f.puts(" charset_map['#{can}'.freeze] = '#{sys}'.freeze")}
f.puts("end")
end
end