Re: pipes

moi wrote:
AFAIK, writes of machine-words are atomic.

That depends on the silicon it is running on. While I don't know of any today that aren't, don't depend on this for tomorrow.

Reads/writes to disks are atomic, too; (modulo pagesize). This can only be
violated by a hardware crash.

This isn't true. There exists hardware where each byte is read by spin loops. Loops can get interrupted. Also there is hardware where each byte is read by interrupt. Interrupts can be blocked or higher priority ones arrive. And it may not be true even for DMA hardware as usually there is a reset command that can be issued to the hardware that will abort a transfer in progress. Also I believe you meant to say modulo device sector size. And you have totally forgotten write with read back check where the read back fails, the driver may do other things before it tries a rewrite and re check, or it may even spare a sector.
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