The ex shall conform to volume of Guidelines

Prepare ex by taking the following actions:

Suppress writing prompts and informational messages.

Ignore and assume the type incapable.

On any system, it shall be an error to specify more than a single option.

Determine the interpretation of single behavior, the classification, and the detection of boundaries.

ex shall not write or text.
ex shall behave.

Otherwise:
all input shall be discarded.

the effect shall be as if the ex was nonexistent.

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Found poem (erasure) from Linux Man Pages
Original text at:
https://man7.org/linux/man-pages/man1/ex.1p.html