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From: PRC on 21 Apr 2008 00:50
---------------------------------------------------------------------------
$cat <<<'Mary has a little lamb!'
Mary has a little lamb!

---------------------------------------------------------------------------
There is an unexpected '\n' in the end. Unlike echo, cat won't output
a <newline>
after the string. So where does the trailing '\n' come from? Maybe it
is related
to the Here String. But it is not mentioned in the bash manual.

Best Regards,
PRC
Apr 21, 2008
From: Barry Margolin on 21 Apr 2008 01:37
In article
<1c675e01-8ead-491d-840f-a5b9192d67fe(a)u12g2000prd.googlegroups.com>,
PRC <panruochen(a)gmail.com> wrote:

> ---------------------------------------------------------------------------
> $cat <<<'Mary has a little lamb!'
> Mary has a little lamb!
>
> ---------------------------------------------------------------------------
> There is an unexpected '\n' in the end. Unlike echo, cat won't output
> a <newline>
> after the string. So where does the trailing '\n' come from? Maybe it
> is related
> to the Here String. But it is not mentioned in the bash manual.

Sounds like a bug in the man page. Most programs expect text input to
be newline-terminated, and it would be a pain if you always had to
include an explicit newline in here strings, so the newline is added
automatically.

--
Barry Margolin, barmar(a)alum.mit.edu
Arlington, MA
*** PLEASE post questions in newsgroups, not directly to me ***
*** PLEASE don't copy me on replies, I'll read them in the group ***
From: pk on 21 Apr 2008 03:54
On Monday 21 April 2008 06:50, PRC wrote:

> ---------------------------------------------------------------------------
> $cat <<<'Mary has a little lamb!'
> Mary has a little lamb!
>
> ---------------------------------------------------------------------------
> There is an unexpected '\n' in the end. Unlike echo, cat won't output
> a <newline> after the string. So where does the trailing '\n' come from?
> Maybe it is related to the Here String. But it is not mentioned in the
> bash manual.

Well, since the <<< construct accepts strings *only on the same line*, I
think the \n is implied, since it would be difficult to differentiate the
case where it's wanted and where it's not.
However, it seems you are using bash, so I think you can use something like

cat <(printf "%s" "Mary had a little lamb")

to achieve the same result. Or, of course, just

printf "%s" "Mary had a little lamb"

--
All the commands are tested with bash and GNU tools, so they may use
nonstandard features. I try to mention when something is nonstandard (if
I'm aware of that), but I may miss something. Corrections are welcome.
From: Florian Kaufmann on 21 Apr 2008 06:54
> Well, since the <<< construct accepts strings *only on the same line*, I

Why you think is that so?

$ cat <<< 'hello
> test'
hello
test
$ $0 --version
GNU bash, version 3.2.33(18)-release (i686-pc-cygwin)
Copyright (C) 2007 Free Software Foundation, Inc.
From: Florian Kaufmann on 21 Apr 2008 06:56

The previous post was mysteriously ill formated.

$ cat <<< 'hello
> test'
hello
test

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