Re: [netrexx-pipelines] Strangeness when filtering linux stty output

[Rony G. F. <Ron...@wu...>]

On 31.07.2023 12:57, Marc Remes wrote:
> a 'redirected pipe' is a program that has its stdin (or stdout/stderr) redirected.
>
> For example 'echo dog | cat', here cat is reading its stdin from the stdout of the echo command,
> The cat process is not connected to a tty, hence stty has no effect.
>
> The pipelines 'command' stage does exactly that: a java process that runs a program with its 
> stdin/stdout redirected.

According to "https://linux.die.net/man/1/stty" "stty --all" would print all settings (to stdout I 
assume).

---rony



>
> On 7/31/23 02:05, J Leslie Turriff wrote
>>     Sorry, I don't understand.  When I run stty --all in bash (no redirection) I
>> get seven lines of output on stdout; when I run it as an operand of the
>> command stage I get no lines.  What is the redirected pipe you're referring
>> to?
>>
>> Leslie
>>
>> On 2023-07-30 12:56:29 Marc Remes wrote:
>>> Hi Leslie,
>>>
>>> because a redirected pipe is not a tty, stty has no effect (and no output).
>>>
>>> Marc
>>>
>>> On 7/29/23 09:39, J Leslie Turriff wrote:
>>>> Marc,
>>>>     stty is not the same as tty; tty is a device, but stty is a tool to
>>>> query or change a tty's settings.
>>>>
>>>> On 2023-07-28 06:35:18 Marc Remes wrote:
>>>>> Hi Leslie,
>>>>>
>>>>> A redirected pipe is not a tty. That's why the output is empty.
>>>>> try pipe 'command tty | console'
>>>>> There are methods to connect a pseudo tty, but I don't think we need to
>>>>> adapt njpipes to support that.
>>>>>
>>>>> ref: https://gamlor.info/posts-output/2021-05-29-tty-in-java/en/
>>>>>
>>>>> Marc