ps 等程序的选项的三种风格
- unix options
- bsd options
- gnu long options
unix options, which may be grouped and must be preceded by a dash.(必须有短线-)
bsd options, which may be grouped and must not be used with a dash.(bsd风格的不能有dash)
gnu long options, ...must be preceded by two dashes.
precede:
vt.
领先, 先于..., 在...之前, 在...前面. 如上面的, 可以用主动语态也可以用被动语态:
a dash must precede options in unix options.
may:
可以有两种用法(两种意思):
- 表示可能.
you may be required.. - 表示可以
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