>"echo '60016000526001601ff3' | xxd -r -p | zig build run -Doptimize=ReleaseFast" is much faster than "echo '60016000526001601ff3' | xxd -r -p | ./zig-out/bin/count-bytes" (compiling + running the program is faster than just running an already-compiled program)
>When you execute the program directly, xxd and count-bytes start at the same time, so the pipe buffer is empty when count-bytes first tries to read from stdin, requiring it to wait until xxd fills it. But when you use zig build run, xxd gets a head start while the program is compiling, so by the time count-bytes reads from stdin, the pipe buffer has been filled.
>Imagine a simple bash pipeline like the following: "./jobA | ./jobB". My mental model was that jobA would start and run to completion and then jobB would start with jobA’s output as its input. It turns out that all commands in a bash pipeline start at the same time.