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* Re: -displayfd outputting some garbage?
       [not found] <589A6A71.4000703@gmail.com>
@ 2017-02-08  1:02 ` Matt D.
  2017-02-09  0:44   ` Jon Turney
  0 siblings, 1 reply; 2+ messages in thread
From: Matt D. @ 2017-02-08  1:02 UTC (permalink / raw)
  To: cygwin-xfree

This is causing issues where I try to perform:

echo $(cat .display)

Which results in:

bash: warning: command substitution: ignored null byte in input
0


Matt D.

On 2/7/2017 7:46 PM, Matt D. wrote:
> I have an xinit script which outputs the display id to a file with the
> following option:
>
> xinit .. -displayfd 3 3>$HOME/.display
>
> This outputs correctly '0' but appends 0x00 and 0x0A. Why is it
> outputting a null byte and this 0x0A?
>
>
> Matt D.

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^ permalink raw reply	[flat|nested] 2+ messages in thread

* Re: -displayfd outputting some garbage?
  2017-02-08  1:02 ` -displayfd outputting some garbage? Matt D.
@ 2017-02-09  0:44   ` Jon Turney
  0 siblings, 0 replies; 2+ messages in thread
From: Jon Turney @ 2017-02-09  0:44 UTC (permalink / raw)
  To: cygwin-xfree; +Cc: Matt D.

On 08/02/2017 01:02, Matt D. wrote:
> On 2/7/2017 7:46 PM, Matt D. wrote:
>> I have an xinit script which outputs the display id to a file with the
>> following option:
>>
>> xinit .. -displayfd 3 3>$HOME/.display

Thanks for reporting this.

For future issues, can I ask you to use the cygwin list, per [1]

[1] https://cygwin.com/ml/cygwin-xfree-announce/2015-03/msg00001.html

I hope you mean ' xinit -- -displayfd 3 3>$HOME/.display'

>> This outputs correctly '0' but appends 0x00 and 0x0A. Why is it
>> outputting a null byte and this 0x0A?

Yeah, this seem to be a bug in xinit (which needs to insert itself into 
the displayfd pipeline to learn the display number for it's own purposes)

$ X -displayfd 3 3>~/.display
[...]
$ xxd ~/.display
00000000: 300a                                     0.

$ xinit -- -displayfd 3 3>~/.display
[...]
$ xxd ~/.display
00000000: 3000 0a                                  0..

> This is causing issues where I try to perform:
>
> echo $(cat .display)
>
> Which results in:
>
> bash: warning: command substitution: ignored null byte in input
> 0

This warning is new in bash 4.4, I think.

I think this is a just a warning though, and shouldn't actually cause 
any issues?

-- 
Jon Turney
Volunteer Cygwin/X X Server maintainer

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^ permalink raw reply	[flat|nested] 2+ messages in thread

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2017-02-08  1:02 ` -displayfd outputting some garbage? Matt D.
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