Re: [9fans] echo -n

[Martin Neubauer <m.ne@gmx.net>]

* arisawa@ar.aichi-u.ac.jp (arisawa@ar.aichi-u.ac.jp) wrote:
> Hello,
>
> I have a question:
> echo -n
> writes 0 length byte to stdout.
> Is this intentional specification?
>
> If it is, what is intended for the specification?

Hello,

As I see it, echo copies its arguments to stdout, followed by a newline. The
`-n' option suppresses this newline. Without looking at the source, it seems
echo initiates the write, writes the arguments (if any), writes a newline
(if not disabled), and ends the write resulting in a zero-length write for
`echo -n'. It could probably be possible to change echo to only do the write
if there is anything to output, but I'm not aware of any formal
specification of that case. Also, there might be scripts that rely on
exactly that behaviour. Maybe a shell function checking the arguments before
calling echo would be a cleaner solution.

	Martin