🚀 go-pugleaf

In article <1993Jan22.185326.679@cine88.cineca.it>, marcello@deis20.cineca.it (Marcello Dalpasso) writes:
|> Is there any wizard on the net being so kind to summarize to me the usage of
|> named pipes?!
	The basic advantage is having a filesystem node to use and
hence two unrelated processes can be communicating much like any
other IPC. It is not like "unamed" pipes which can exist only between
related processes (like parent-child).

|> 
|> In particular, I would make something like this:
|> 
|> cp file named-pipe
|> 
|> and get "file" passed to lpr, i.e. named-pipe == | lpr
|> 
   Sure it can be done.

|> Thanks in advance for any help, preferably via e-mail
|> 
|> -- 
|> 	Marcello Dalpasso (e-mail: marcello@deis20.cineca.it)
|> 	D.E.I.S. - Department of Electronics, Computer Science and Systems
|> 	Viale Risorgimento 2, I-40136 Bologna, Italy			
|> 	Phone: +39-51-644-3015 (fax: +39-51-644-3073)

I am not sure what exactly you trying to achieve but anyway one
way to use "named pipes" & lpr together is as follows:

1) assume you have created a named pipe "/tmp/Fifo" using "mknod -p"

2) Lets say your printer name is lp then we can do the following to
read from the fifo:
	cat /tmp/Fifo | /usr/ucb/lpr -P lp

	Now you will notice that it is waiting for data
(remember it is a pipe)

3) now you can copy the data to be printed into the named pipe as
you wanted to do (i.e using cp) as shown below:

	cp /etc/passwd /tmp/Fifo


hope this info helps.
	Yes, you have used named pipes & lpr together.
raj
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