Thanks for the response and suggestion.
From eshell,
     λ xdg-open file.txt
exits immediately, without opening file.txt, and
     λ cat | xdg-open file.txt | cat
shows the same behavior, but
     λ setsid -w xdg-open file.txt
opens the file as expected.
Hope this helps,
Jeff



On Tue, Nov 22, 2022 at 12:20 PM Jim Porter <jporterbugs@gmail.com> wrote:

> On 11/20/2022 9:14 PM, Jeff Kowalski wrote:
> > While I cannot help to craft the solution (I'm limited by my knowledge
> > of internals here), I'm very happy to help test proposals.  It seemed
> > there was a hint of a solution developed in this thread.
>
> This is a hacky workaround, but if it works for you, it would help prove
> a strategy to fix this:
>
>    ~ $ cat | xdg-open file.txt | cat
>
> The above forces 'xdg-open' to be run with pipes for its stdin and
> stdout. I believe the issue is that when 'xdg-open' sees a PTY for
> stdin/stdout, it seems to assume that the PTY will live for a long time;
> however, in Eshell, it will close the PTY as soon as 'xdg-open' returns,
> which breaks things.
>
> A real fix would be to tell Eshell that certain programs, like xdg-open,
> should never use PTYs. (There used to be a variable called
> 'eshell-needs-pipe' that did something similar to this, but after
> changing how Eshell connects processes, it was no longer needed.)
>