echo "!!!! Please make sure that you put INPUT.fdf, *.psf and POSCAR files here"

[Hongyi Zhao]

Hi all,

What's the mean for using `!' in echo, say, for the following example:

echo "!!!! Please make sure that you put INPUT.fdf, *.psf and POSCAR
files here"

You can find the command from here:

http://139.179.64.2/mt2/SIESTA-PHON/PHON/1_SCRIPTS/phon_input

Regards
--
.: Hongyi Zhao [ hongyi.zhao AT gmail.com ] Free as in Freedom :.

[Janis Papanagnou]

On 15.06.2015 07:06, Hongyi Zhao wrote:
> Hi all,
>
> What's the mean for using `!' in echo, say, for the following example:
>
> echo "!!!! Please make sure that you put INPUT.fdf, *.psf and POSCAR
> files here"

The same meaning as the word "Please": a plain text. Repeated four times
to draw attention.

I suppose you are maybe still using bash and are wondering about errors
or strange output you see? - Change your shell, use ksh, if you don't
want your quoted literal "!" in text be interpreted, or change all your
programs to use single quotes in strings where you intend to use this
normal character "!" in your texts. (Or read the manual; there might be
an option to disable this IMO broken default behaviour in bash.)

Janis

[Chris F.A. Johnson]

On 2015-06-15, Hongyi Zhao wrote:
> Hi all,
>
> What's the mean for using `!' in echo, say, for the following example:
>
> echo "!!!! Please make sure that you put INPUT.fdf, *.psf and POSCAR
> files here"

It prints an exclamation mark. What else would you expect?

At the command line, however, if you are unfortunate enough to have
one in $histchars, it does all sorts of weird things. Remove it at
once! Put this in your .bashrc:

histchars=${histchars/!/}

Or, at the command line:

unset histchars


--
Chris F.A. Johnson

[Janis Papanagnou]

On 15.06.2015 07:22, Chris F.A. Johnson wrote:
> On 2015-06-15, Hongyi Zhao wrote:
>> Hi all,
>>
>> What's the mean for using `!' in echo, say, for the following example:
>>
>> echo "!!!! Please make sure that you put INPUT.fdf, *.psf and POSCAR
>> files here"
>
> It prints an exclamation mark. What else would you expect?
>
> At the command line, however, if you are unfortunate enough to have
> one in $histchars, it does all sorts of weird things. Remove it at
> once! Put this in your .bashrc:
>
> histchars=${histchars/!/}

That's ineffective if histchars is empty (or not defined).

>
> Or, at the command line:
>
> unset histchars

Also ineffective in my environment.

I'm running GNU bash, version 4.2.25

Janis

[Hongyi Zhao]

On Mon, 15 Jun 2015 07:47:41 +0200, Janis Papanagnou wrote:

> I suppose you are maybe still using bash and are wondering about errors
> or strange output you see?

Yes.

> - Change your shell, use ksh,

I'll give it a try.

> if you don't
> want your quoted literal "!" in text be interpreted, or change all your
> programs to use single quotes in strings where you intend to use this
> normal character "!" in your texts. (Or read the manual; there might be
> an option to disable this IMO broken default behaviour in bash.)

See the strange output for my case:

werner@debian:~$ echo "!"
bash: !: event not found
werner@debian:~$ echo "!!"
echo "gedit "
gedit
werner@debian:~$ echo "!!!"
bash: !": event not found
werner@debian:~$ echo "!!!!"
echo "echo "gedit "echo "gedit ""
echo gedit echo gedit
werner@debian:~$

[Janis Papanagnou]

On 15.06.2015 11:11, Hongyi Zhao wrote:
> On Mon, 15 Jun 2015 07:47:41 +0200, Janis Papanagnou wrote:
>
>> I suppose you are maybe still using bash and are wondering about errors
>> or strange output you see?
>
> Yes.
>
>> - Change your shell, use ksh,
>
> I'll give it a try.
>
>> if you don't
>> want your quoted literal "!" in text be interpreted, or change all your
>> programs to use single quotes in strings where you intend to use this
>> normal character "!" in your texts. (Or read the manual; there might be
>> an option to disable this IMO broken default behaviour in bash.)
>
> See the strange output for my case:

You may have missed that part: "[...] use *single* quotes [...]"

[Huibert Bol]

That is to be expected with history substitutions enabled, you can
easily turn it of: set +H

--
Huibert
"Okay... really not something I needed to see." --Raven

[Chris F.A. Johnson]

On 2015-06-15, Janis Papanagnou wrote:
> On 15.06.2015 07:22, Chris F.A. Johnson wrote:
>> On 2015-06-15, Hongyi Zhao wrote:
>>> Hi all,
>>>
>>> What's the mean for using `!' in echo, say, for the following example:
>>>
>>> echo "!!!! Please make sure that you put INPUT.fdf, *.psf and POSCAR
>>> files here"
>>
>> It prints an exclamation mark. What else would you expect?
>>
>> At the command line, however, if you are unfortunate enough to have
>> one in $histchars, it does all sorts of weird things. Remove it at
>> once! Put this in your .bashrc:
>>
>> histchars=${histchars/!/}
>
> That's ineffective if histchars is empty (or not defined).

If histchars is empty or not defined, then there's no problem to be solved.

--
Chris F.A. Johnson

[Stephane Chazelas]

2015-06-15 16:18:45 -0400, Chris F.A. Johnson:

$ bash --norc
bash-4.3$ echo "${histchars-unset}"
unset
bash-4.3$ echo "!!"
echo "echo "${histchars-unset}""
echo unset
bash-4.3$ histchars=${histchars/!/}
bash: !/}: event not found
bash-4.3$ histchars=${histchars/\!/}
bash-4.3$ echo "!!"
!!

So looks like the "problem" is when $histchars is unset (like it
is by default) and setting histchars to the empty string fixes
the "problem".

--
Stephane

[Eric]

Well...

eric@bruno [ ~ ]$ set | grep histchars
eric@bruno [ ~ ]$ !!
set | grep histchars
eric@bruno [ ~ ]$ histchars=""
eric@bruno [ ~ ]$ set | grep histchars
histchars=
eric@bruno [ ~ ]$ !!
-bash: !!: command not found
eric@bruno [ ~ ]$

So apparently it defaults if not defined, but if set to the empty
string, nothing happens. Of course there are some bash options that
might change this.

Eric
--
ms fnd in a lbry

[Janis Papanagnou]

There is! - echo $histchars provides an empty result per default.
Still the problem exists. As said, unset'ing also doesn't help.
As others pointed out, setting it explicitly to a null-string
seems to fix that issue.

Janis