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Re: My script almost works but spams the terminal its launched from if useing dash.

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On 04/16/2016 12:11 PM, Aero Maxx wrote:
> On 16/04/2016 17:45, Gene Heskett wrote:
>> On Saturday 16 April 2016 12:01:28 Aero Maxx wrote:
>>
>>> On 16/04/2016 16:23, Gene Heskett wrote:
>>>> But when I run it with dash, it doesn't seem to work right, and
>>>> spams the terminal with its error messages.  One that appears to
>>>> kill its function is the bashism of using [[ ]] to surround string
>>>> variables, reported like this:
>>>> bin/mailwatcher: 64: bin/mailwatcher: [[: not found
>>>> bin/mailwatcher: 70: bin/mailwatcher: [[: not found
>>>> bin/mailwatcher: 77: bin/mailwatcher: [[: not found
>>> dash isn't the same as bash, as it has a limited set of instructions
>>> or commands it can do.
>>>
>>> But I too would be interested to know if it is possible to get it to
>>> work in dash, I don't believe it is, but I am happy to be corrected
>>> or proved wrong.
>>>
>>>> And finally, once its working with either shell, how do I shut it up
>>>> totally?  Even the above command line launch fails as it outputs to
>>>> that shell, a newline for every incoming mail which gradually
>>>> scrolls any output that was on-screen, offscreen without leaving a
>>>> prompt until I tap the return key to restore it.
>>> Also isn't the command you are running supposed to be as follows ?
>>>
>>>> bin/mailwatcher 2>&1 > /dev/null &
>>>>
>> Is the space you inserted into my line between the > and the /dev/null a
>> game changer? In either bash or dash?  Its been a while since I last
>> read the bash docs, but I don't recall there was any emphasis on that.
>>
> I'm sorry I was a bit too eager to reply and neglected to change what 
> I had pasted in.
>
> I meant to say could you try this
>>
>> bin/mailwatcher > /dev/null 2>&1 &
>
Yes, this is the correct incantation.  The difference is very subtle.  
With ... 2>&1 >/dev/null, the error output is redirected to be the same 
as the standard output, and then the standard output is redirected to 
/dev/null -- leaving the error output still going to the original 
standard output (terminal).  With ... >/dev/null 2>&1 The standard 
output is redirected first, and the the error output is sent to the same 
place as the standard output, resulting in both going to /dev/null.  The 
order of redirection is important to the end results in this case.
> This email has been checked for viruses by Avast antivirus software.
> https://www.avast.com/antivirus
>

-- 
Mike

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My script almost works but spams the terminal its launched from if useing dash. Gene Heskett <gheskett@shentel.net> - 2016-04-16 17:30 +0200
  Re: My script almost works but spams the terminal its launched from  if useing dash. Aero Maxx <aero.maxx.d@gmail.com> - 2016-04-16 18:10 +0200
    Re: My script almost works but spams the terminal its launched from if useing dash. Gene Heskett <gheskett@shentel.net> - 2016-04-16 18:50 +0200
      Re: My script almost works but spams the terminal its launched from  if useing dash. Aero Maxx <aero.maxx.d@gmail.com> - 2016-04-16 19:20 +0200
        Re: My script almost works but spams the terminal its launched from if useing dash. Gene Heskett <gheskett@shentel.net> - 2016-04-17 00:50 +0200
        Re: My script almost works but spams the terminal its launched from  if useing dash. Michael Milliman <michael.e.milliman@gmail.com> - 2016-04-17 08:30 +0200
          Re: My script almost works but spams the terminal its launched from if  useing dash. Jeremy Nicoll <jn.ml.dbn.25@letterboxes.org> - 2016-04-17 13:00 +0200
            Re: My script almost works but spams the terminal its launched from if useing dash. "Thomas Schmitt" <scdbackup@gmx.net> - 2016-04-17 13:50 +0200
              Re: My script almost works but spams the terminal its launched from if  useing dash. Jeremy Nicoll <jn.ml.dbn.25@letterboxes.org> - 2016-04-17 15:10 +0200
                Re: My script almost works but spams the terminal its launched from if useing dash. "Thomas Schmitt" <scdbackup@gmx.net> - 2016-04-17 15:30 +0200
                Re: My script almost works but spams the terminal its launched from  if useing dash. Michael Milliman <michael.e.milliman@gmail.com> - 2016-04-17 15:40 +0200
                Re: My script almost works but spams the terminal its launched from if  useing dash. Jeremy Nicoll <jn.ml.dbn.25@letterboxes.org> - 2016-04-17 16:40 +0200
            Re: My script almost works but spams the terminal its launched from  if useing dash. Michael Milliman <michael.e.milliman@gmail.com> - 2016-04-17 15:30 +0200
          Re: My script almost works but spams the terminal its launched from if useing dash. Gene Heskett <gheskett@shentel.net> - 2016-04-17 13:50 +0200
        Re: My script almost works but spams the terminal its launched from  if useing dash. Andrew McGlashan <andrew.mcglashan@affinityvision.com.au> - 2016-04-22 06:30 +0200
          Re: My script almost works but spams the terminal its launched from  if useing dash. Michael Milliman <michael.e.milliman@gmail.com> - 2016-04-22 07:00 +0200
            Re: Re: My script almost works but spams the terminal its launched  from if useing dash. Clive Standbridge <list-user@tgstandbridges.plus.com> - 2016-04-22 11:40 +0200
          Re: My script almost works but spams the terminal its launched from if useing dash. Gene Heskett <gheskett@shentel.net> - 2016-04-22 10:30 +0200
          Re: My script almost works but spams the terminal its launched from  if useing dash. David Wright <deblis@lionunicorn.co.uk> - 2016-04-22 13:10 +0200
  Re: My script almost works but spams the terminal its launched from if useing dash. Sven Joachim <svenjoac@gmx.de> - 2016-04-16 18:50 +0200
    Re: My script almost works but spams the terminal its launched from if useing dash. Gene Heskett <gheskett@shentel.net> - 2016-04-16 19:10 +0200
      Re: My script almost works but spams the terminal its launched from  if useing dash. Linux-Fan <Ma_Sys.ma@web.de> - 2016-04-16 19:30 +0200
      Re: My script almost works but spams the terminal its launched from if useing dash. "Thomas Schmitt" <scdbackup@gmx.net> - 2016-04-16 20:10 +0200
        Re: My script almost works but spams the terminal its launched from if useing dash. Gene Heskett <gheskett@shentel.net> - 2016-04-17 01:10 +0200
          Re: My script almost works but spams the terminal its launched from  if useing dash. David Wright <deblis@lionunicorn.co.uk> - 2016-04-17 04:30 +0200
            Re: My script almost works but spams the terminal its launched from if useing dash. Gene Heskett <gheskett@shentel.net> - 2016-04-17 06:50 +0200
              Re: My script almost works but spams the terminal its launched from  if useing dash. David Wright <deblis@lionunicorn.co.uk> - 2016-04-18 16:00 +0200
                Re: My script almost works but spams the terminal its launched from if useing dash. Gene Heskett <gheskett@shentel.net> - 2016-04-18 20:50 +0200
          Re: My script almost works but spams the terminal its launched from if useing dash. "Thomas Schmitt" <scdbackup@gmx.net> - 2016-04-17 14:10 +0200
          Re: My script almost works but spams the terminal its launched from if useing dash. "Thomas Schmitt" <scdbackup@gmx.net> - 2016-04-17 14:10 +0200
            Re: My script almost works but spams the terminal its launched from if useing dash. Gene Heskett <gheskett@shentel.net> - 2016-04-17 15:20 +0200
              Re: My script almost works but spams the terminal its launched from if useing dash. "Thomas Schmitt" <scdbackup@gmx.net> - 2016-04-17 16:40 +0200

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