This article is from the Amiga FAQ, by Ignaz Kellerer with numerous contributions by others.
*Q:* When I try the command `List SYS: | More' I get an error PIPE: Unknown command
I have `PIPE:' mounted, what's wrong?
*A:* AmigaShell is referring to the command `Pipe' in the error, not the `PIPE:' device. You haven't installed the commands in the ShellTools archive.
*Q:* I get a requester that says Please insert volume PIPE: in any drive
when I try any of the command examples.
*A:* `PIPE:' is not mounted. Try `Mount PIPE:'. If that doesn't work, refer to your AmigaDOS manual or a friend that knows how to mount devices.
*Q:* When I try any of the examples the More window pops up but nothing is shown/I get an error afterwards/More pops up a file requester.
*A:* You are not using the standard AmigaOS `More' command. Either use another name or install a command that supports pipes. Possibilities are the C= More, Less, or Most for example.
*Q:* With use of PIPE:, sometimes characters get lost. What happened?
*A:* Up to OS 3.1, the queue-handler has some bugs which don't allow a really foolproof transmission of data. A compatible replacement for the queue-handler can be founbd on Aminet, `util/sys/HWGQueue.lha'.
*Q:* None of these happen but it still doesn't work as you described.
*A:* Are you using OS 2.04 later? Are you using the standard AmigaShell? Try with all extras disabled.