Add/Remove BOM

bom_util

#!/usr/bin/ruby

require "optparse"

mode = :help

opt = OptionParser.new
opt.on("-a", "Add BOM"){|v| mode = :add}
opt.on("-d", "Delete BOM"){|v| mode = :delete}
opt.parse!(ARGV)

case mode
when :add
 STDOUT.binmode
       lines = readlines
       unless lines[0] =~ /^\M-o\M-;\M-?/ then
               print "\xEF\xBB\xBF"
       end
       print lines

when :delete
 STDOUT.binmode
       lines = readlines
 lines[0].sub!(/^\xEF\xBB\xBF/, '')
 print lines

when :help
       STDERR.puts opt.help
end