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Grok provides a meaningful answer.<br>
<hr width="100%" size="2"><span style="white-space: pre-wrap">Brian Kernighan is credited with demonstrating the famous spell checking pipeline using Unix commands like cat | tr | sort | uniq | comm (or similar variations). In a classic 1970s Bell Labs video titled "The UNIX Operating System," he showcased pipelines for spell checking as an early example of Unix's power. The video uses a pipeline like makewords sentence | lowercase | sort | unique | mismatch to extract words, lowercase them, sort, remove duplicates, and compare against a dictionary—concepts that directly inspired modern equivalents with tr for translation, uniq for deduplication, and comm for comparison. This approach highlights Unix's philosophy of combining simple tools for complex tasks, and while the exact commands evolved, the core idea stems from Kernighan's presentation. The original spell command from 1975, written by Stephen C. Johnson with improvements by Douglas McIlroy, used a similar internal logic but not this exact pipeline.</span>
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Heinz<br>
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<div class="moz-cite-prefix">On 9/3/2025 5:53 AM, Dan Cross via TUHS
wrote:<br>
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cite="mid:CAEoi9W79MF+8OmOAXaUAAs+KfgQLJnriOiG2FaZK4Gosx8G54Q@mail.gmail.com">
<pre wrap="" class="moz-quote-pre">On Wed, Sep 3, 2025 at 3:47 AM Diomidis Spinellis via TUHS
<a class="moz-txt-link-rfc2396E" href="mailto:tuhs@tuhs.org"><tuhs@tuhs.org></a> wrote:
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<pre wrap="" class="moz-quote-pre">In Brian Kernighan's amazing VCF talk that Arnold Robbins shared
yesterday, bwk mentions that Steve N[uancen?] came up with the famous
spell checking pipeline: cat | tr | sort | uniq | comm
<a class="moz-txt-link-freetext" href="https://www.youtube.com/watch?v=WEb_YL1K1Qg&t=1396s">https://www.youtube.com/watch?v=WEb_YL1K1Qg&t=1396s</a>
Anybody knows the correct name of that person? ChatGPT only
hallucinates many wrong ones.
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As others have pointed out, it was Steve Johnson. I wanted to mention
that he did say Steve Johnson in the video as well, though I can see
how one might (mis)hear differently; I think that's just an artifact
of the audio.
- Dan C.
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