Watch the variables being used in a function. If you notice a function using an out-of-scope variable more than once, store it in a local variable and use that instead.
仔细检查函数中所有使用的变量，如果有一个变量不是当前作用域定义的，而且使用了不止一次，那么我们就应该把这个变量保存在局部变量中，而使用这个局部变量来进行读写操作。
Tcsh provides the built-in shell variable watch, which makes it easy to view who is logging in and out of the system.
tcsh提供了内置shell变量watch，可以通过它查看正在使用系统的用户。
It allows you to watch which modules are being executed, which SQL statements are executing, and which variable values change as you navigate the Web site.
它允许您查看哪些模块正被执行，哪些sql语句正在执行，以及在您浏览Web站点时哪些变量值发生更改。
应用推荐