测试脚本被调用的参数数量是否正确

  1 E_WRONG_ARGS=65
  2 script_parameters="-a -h -m -z"
  3 #                  -a = all, -h = help, 等等.
  4 
  5 if [ $# -ne $Number_of_expected_args ]
  6 then
  7   echo "Usage: `basename $0` $script_parameters"
  8   # `basename $0` 是这个脚本的文件名.
  9   exit $E_WRONG_ARGS
 10 fi