求助，命令参数的语法问题

vivian2086

man 一个命令时，语法格式那里，[ ]括起来的是可选参数，那{ }和< >括起来的是什么意思？

man man 可以看到的说明只有[ ]和下划线，粗体字等的说明：

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       bold text          type exactly as shown.
       italic text        replace with appropriate argument.
       [-abc]             any or all arguments within [ ] are optional.
       -a|-b              options delimited by | cannot be used together.
       argument ...       argument is repeatable.
       [expression] ...   entire expression within [ ] is repeatable.

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Jockey

我没注意到有过花&尖括号...

vivian2086

<>好像是必选