Pipe Logic

Delightfully useless epiphany: Suppose the null-byte is an electron. Then, /dev/zero provides an infinite supply of electrons and /dev/null has an infinite appetite for them. Let’s call these devices Vss and Vdd, respectively.

In this model, a UNIX pipe acts like a wire, that is, a conductor with parasitic capacitance. If the pipe is connected to Vss, its pipe buffer in kernel space quickly fills up with null-bytes, and the pipe acts like a negatively charged metal plate. If it is connected to Vdd, the pipe buffer is drained, and the pipe acts like a positively charged metal plate.

Pipes may thus carry logic signals: A pipe that is filled with null-bytes corresponds to a logic zero, and a pipe that is completely empty corresponds to a logic one. A pipe that contains some null-bytes, but is neither full nor empty, corresponds to a voltage in the undefined range, and will act as a one or a zero depending on how we measure it.

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