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50th Anniversary Of '|'

31 points by nolta ↗ HN
Apparently today is the 50th anniversary of using '|' for connecting shell pipelines. It was introduced in v4 of the Thompson shell, whose manpage is dated 1973-04-18 [1]. Previously the syntax for 'a | b' was `a >b>` [2].

[1]: https://www.in-ulm.de/~mascheck/bourne/v4/

[2]: https://www.in-ulm.de/~mascheck/bourne/v3/

6 comments

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surprisetalk
Happy anniversary!

I'm not sure if it's true, but I've heard that the inspiration for Unix pipes came from APL.

AITree
congratulations on 50 th aniversary of "I"
ralferoo
Interesting that both | and ^ were supported, but | took over and ^ is still unused by the shell.

I wonder if ^ was deprecated because of the likelihood it'd be commonly used at the start of a regexp for grep, but | used to provide alternatives in a regexp was probably much less frequently used and so having to quote is was less of a problem than for ^.

Also interesting that the v3 format had both input and output filters, which is just semantic repositioning of the commands.

samstave
The ' ^ ' should be used going forward by CLI AI wrappers to mean "use the above and then | to the following"

So if you prompt, you can just "^ | table" to say "Now use the above and show me in a table." ; or just " ^ table " should suffice, ideally.

deadly_syn
You could try

!! | some_command

Should theoretically work as youre describing in bash today!