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1. tptacek · 1790529889 · focus · HN ↗

   Hmm. What a great question.

       while(1) { fork(); } 
   

   Must have meant something to me, because it was in my Usenet sig. And then:

       exit(main(kfp->kargc, argv, environ));
   

   from FreeBSD crt0; kind of a big moment for me to realize there was more C code underneath main().

   Then:

       statements: /*E*/ | statement statements
   

   The moment Yacc clicked for me; that line was profound but a more accurate depiction of the moment was realizing that all you were doing with the parser generator was building a tree, and that's what the side effects of each production were for: returning and plugging in tree nodes.

   If there was a single line I could come up with for "double the size of the hash table when it fills up", that'd deserve a slot here.

   Then, of course (we get to cheat because assembly):

       jmp .call
       .pop: pop esi
       ...
       .call: call .pop
   

   The "delta offset" trick, which I believe came from x86 virus culture but was universal in 90s overflow exploits as a way to get position-independent references to strings and other memory things.

   For sure:

       void walk(node *n) { if(!n) return; walk(n->left); visit(n); walk(n->right); }
   

   I should figure out a way to fit a write-select(2) into a line because that's another "oh shit" moment for me.

   Similarly: when Vern Paxson explained to me that he'd implemented TCP reassembly by simply opening up a file and using "seek" to place incoming segments in the right position. I could probably golf that down to a line! But it would be an annoying line.

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