该命令与示例 1 所做的工作相同，但在本例中，selpg 读取标准输入，而标准输入已被 shell／内核重定向为来自“input_file”而不是显式命名的文件名参数。

This does the same as example 1, but in this case, selpg is reading its stdin, which has been redirected by the shell/kernel to come from "input_file" instead of an explicitly named filename argument.

youdao

实际上，在大多数由程序员(而不是XML开发人员或数据管理员)编写的文档中，往往使用驼峰式(camel - case)命名法，比如firstName。

In fact, most of the documents that do use camel-case naming, like firstName, are authored by programmers, rather than XML-centric developers or data managers.

youdao

没有命名断言，不过它是隐式的。

The assertion is not named; however, it is implied.

youdao