s h e l l编程最烦人的一项工作是调试问题。有一些方法可以借鉴，但是最好能在问题出现前防止大部分错误，为此应遵循以下规则。 本书简单讲解-The most annoying one shell programming is to debug the problem. There are ways to learn, but the problem is best able to prevent most errors before, this should follow the rules