An awk trick nicely explained. Though it's a trick that I may never use. I recommend this article mostly for the extraordinary pedagogy style.

I was piqued by this, so I went on read Ken Thompson's original article. I am amazed by it. It's a quite surprising application of quine. Don't worry, it doesn't give me a feeling of existential crisis as I still have faith on the beloved fellow compiler workers.

Read about it in https://dl.acm.org/doi/10.1145/358198.358210 .