So I have a need to write data to a POSIX named pipe (aka FIFO). Long story involving a command that doesn't have an option to read data from stdin, but can from a named pipe. I have created the named pipe from Haskell no problem. But I can't use writeFile to write data to it. Worse, it returns: *** Exception: /tmp/bakroller.zD0xHj/fifo: openFile: does not exist (No such device or address) which is completely false, as it *does* exist, and I can cat to it as expected. The call should block until everything is read on the remote end. I thought maybe writeFile is being weird, so I tried: openFile "/tmp/bakroller.zD0xHj/fifo" WriteMode Same thing. There is no logical reason I can see for this behavior. In fact, something must be going to *extra* effort to avoid writing to a named pipe, and I can't work out why. Named pipes are a standard, useful part of a system and shouldn't be ignored like this. Interestingly, readFile works fine on a named pipe. What's going on here? Am I going to have to resort to the System.Posix interface just to be able to write to a named pipe? -- John