def initialize(command)
@cmd = command.to_s
@cmdno = self.class.cmdno
self.class.cmdno += 1
@err = ''
@out = ''
@cid = "%d_%d_%d" % [$$, cmdno, rand(Time.now.usec)]
@begin_out = "__CMD_OUT_%s_BEGIN__" % cid
@end_out = "__CMD_OUT_%s_END__" % cid
@begin_out_pat = %r/#{ Regexp.escape(@begin_out) }/
@end_out_pat = %r/#{ Regexp.escape(@end_out) }/
@begin_err = "__CMD_ERR_%s_BEGIN__" % cid
@end_err = "__CMD_ERR_%s_END__" % cid
@begin_err_pat = %r/#{ Regexp.escape(@begin_err) }/
@end_err_pat = %r/#{ Regexp.escape(@end_err) }/
end