Re: not good proposal: "C-z <letter>" reserved for users

[Jean Louis <bugs@gnu.support>]

* Emanuel Berg via Users list for the GNU Emacs text editor <help-gnu-emacs@gnu.org> [2021-02-20 22:23]:
> Jean Louis wrote:
> 
> >> You can just bring forward an empty tmux pane anytime and
> >> do whatever task there instead.
> >
> > You are so right, but that is supervision of various
> > processes, not suspending of a process.
> 
> You can for example suspend a process like this:
> 
>   $ kill -STOP PID

Sure I know that, since last 20 years. We have to look at those
proposals globally, not personally. Objectively not subjectively.

It is great that some shell providers offer tmux/screen like:
https://blinkenshell.org/wiki/Start

Yet that may not be the case for many other users.

But mentioning tmux/screen is not relevant to suspending a process,
like I have repeated several times. It is not good misleading users
who read this mailing list to think that tmux/screen replaces
something like suspending or continuing of a process.

In Windoze systems, one will invoke process manager or task manager, I
am not sure how it is called. If I remember well that would be with
right mouse click on taskbar or Ctrl-Alt-Del but I am not sure as
Windoze is changing over time. And that will work if there are no
extensive CPU processes, as otherwise quicker suspend is not
possible. So I have no idea for Windoze

For GNU/Linux and BSD derivatives, console and terminal emulators are
extensively used, there are millions of BSD-derivate types of servers
that do not run X, and many will have users who do not have access to
root powers to install some software. However, screen/tmux do not
replace job control, as they offer as main service the continuation of
software being run even when user logs off. Processes in tmux/screen
still run, I know that, as I will often download heavy torrents by
using screen.

To be able to `kill -STOP PID' one has to have access to second
terminal, or double shell or tmux/screen, but the time necessary to
invoke those extra commands may be too long as in that time the
program may already damage data, user may lose data, disk may be
filled completely, files could be deleted by mistake and so
on. Control-Z is used in emergency. Sometimes it may be used to switch
from task to task, but that is just one case use, there are many
different cases uses. 

In Emacs mailing lists people often forget that that Emacs and other
software runs on multiuser computers. Universities, organizations,
various computer providers, website providers, may provide shell
access but not all types of software. Sometimes is impossible to
install everything as user as what you can install as root. Not every
user is using self-owned computer. Not every programming language is
installable. System administrators may disable execution of programs
on user partititions, so user could maybe download executable or
compile it, but never run it or execute it.

Now you say you can do kill -STOP PID, but of course I know, that is
however something you do when you have access to command line. As if
you do have access to command line in that case there is probably no
need to quickly suspend a process by using Control-Z and probably
there is no emergency situation where suspending a process is
necessary. You may go slow by typing many letters, of course, after
first searching for the process PID.

Not every user can install tmux, screen, you name it. Not every user
has Internet access to be able to install it. We have to look at
proposals globally, planetary, not only for those users in developing
countries. Is not objecitve to say that that everybody has Internet
access and that every user can even pay for Internet access.

As a side note to think about: Majority of stationaries with computers
in developing countries in East Africa are NOT connected to
Internet. That means it is harder to find stationary where I can tell
them "please download https://www.example.com/1.pdf" as their
computers are not connected to Internet.

Universities and libraries may have GNU/Linux installed but without
access to installation of software, without access to administrator,
sometimes without an administrator at all.