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Error in bash manual?


From: Jan Carreras Prat
Subject: Error in bash manual?
Date: Sun, 22 Apr 2012 17:47:54 +0200

>From my point of view in the section REDIRECTION of the man manual there
is something technically incorrect:

/dev/tcp/host/port
    If host is a valid hostname or Internet address, and port
    is  an integer port number or service name, bash attempts
    to open a TCP connection to the corresponding socket
/dev/udp/host/port
    If host is a valid hostname or Internet address, and port
    is  an integer port number or service name, bash attempts
    to open a UDP connection to the corresponding socket.


The sentence I disagree with is:
    "bash attempts to open a UDP connection"

The term 'UDP connection' is incorrect since in UDP there aren't any connections
The definition of UDP (man udp) is:
    This  is  an  implementation  of  the User Datagram Protocol described
    in RFC 768. It implements a *connectionless*, unreliable datagram packet
    service.  Packets may be reordered or duplicated before they arrive.

"Conectionless" is the key.  If we search the term "connection" in RFC768 any
results will appear.  Thus, "UDP connection" seems wrong to me, at least in
this context.

Moreover, "attempts to open" seems incorrect to me, because bash does not attemp
to open anything.  Maybe bash "tries to send" or "attempts to send" a UDP
datagram, but does not try to open anything, nor a connection.

To me, it looks like someone has done copy-paste from the block of TCP
(block that is correct, because TCP is connection-oriented) and just changed TCP
word for UDP.  However, UDP is not the same as TCP and one of the differences is
that UDP *does not establish any type of connections*.

So, I propose to change the sentence:
    "bash attemps to open a UDP connection to the corresponding socket"
to:
    "bash attemps to send a UDP datagram to the corresponding socket"

It's seems to me reasonably accurate

Please, feel free to make any suggestions, variations or whatever. Thanks.

Jan Carreras

Note: I sent this mail to address@hidden twelve days ago and I
don't have a response yet. I guess that the next logic step is sending
the mail to address@hidden If I'm wrong please point me to the
right place. Thanks.



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