Execute a command in a separate konsole then let users type commands

Question

I am working on software at a large corporation where I have little control over the overall technologies used, and as a result need to find solutions that will work within the constraints I have.

What I'm working on: I'm developing a UI that lets users launch konsoles with specific environments based on the projects they are working on. We currently have a command (let's call it "setContext") that users run in their konsole manually with a lot of arguments. setContext does a lot of work and sets a lot of environment variables. As part of my constraints, I have to use konsole, tcsh, and this setContext command. All my UI needs to do is compose the setContext command with the proper arguments, open a konsole, and run that command for the user, after what they will be in control.

The command I generate is something like:

konsole -e tcsh -c "setContext --someArgs"

This works, but closes the konsole right away. Using the --noclose option when launching the konsole keeps it open but not interactive.

The commonly accepted solution to this problem, is to append ;bash or ;$SHELL at the end of the command, in my case I have extrapolated it to be ;tcsh.

This is what is suggested in the following links, and many others:

• https://askubuntu.com/questions/20330/how-to-run-a-script-without-closing-the-terminal/1209836#1209836
• https://askubuntu.com/questions/46627/how-can-i-make-a-script-that-opens-terminal-windows-and-executes-commands-in-the
• Run commands in a terminal, then let me type more commands
• https://askubuntu.com/questions/484993/run-command-on-anothernew-terminal-window

This nearly works, as it does indeed keep the konsole open. In fact this is what I have been using for weeks without troubles, however we have noticed that running tcsh after setContext sources all the initialization files again (~/.cshrc, etc..), which resets some of the variables set by setContext.

This needs to work for hundreds of users, and I have no control over the cshrc files, so I need to find a way to keep the konsole open without sourcing these again. I tried tcsh -f but that doesn't preserve the environment.

I have been searching online all afternoon but haven't managed to find a solution. While I understand environments and commands okay, I am no expert and usually work in python. I am resorting to ask here because everything I'm finding is either a re-hash of the answer above, requires to modify cshrc files, or is way above my level and I can't decipher it.

Thanks in advance.

Answer 1

running tcsh after setContext sources all the initialization files again (~/.cshrc, etc..), which resets some of the variables set by setContext.

You could trick tcsh into not reading the ~/.cshrc by pointing the HOME environment variable to some other directory containing a .cshrc which resets HOME to its original value, sources the user's ~/.tcshrc or ~/.cshrc, and then calls your setContext.

Example, using /fake/home as the decoy home directory:

konsole -e sh -c 'REAL_HOME=$HOME HOME=/fake/home exec tcsh'

with /fake/home/.cshrc containing:

setenv HOME "$REAL_HOME"
if (-f ~/.tcshrc) then
   source ~/.tcshrc
else if (-f ~/.cshrc) then
   source ~/.cshrc
endif
setContext
# other aliases and initializations

---

Yes, this is a horrible kludge. Find something better ;-)

Answer 2

A possible workaround I'd like to share is somebody else is in the same situation as I am, is to use qdbus to send commands to another instance of konsole.

It's can be a bit convoluted because in my case I needed to know the Konsole's pid, but it did the trick.

• https://docs.kde.org/stable5/en/applications/konsole/scripting.html
• https://www.linuxjournal.com/content/start-and-control-konsole-dbus

I think I will still use user431397's method in the end because qdbus often gives a warning when sending commands, which could be removed by recompiling, but it's not something I can do, and the warning is annoying me.

I have also discovered yakuake while researching dbus, and it turned out to be installed here, and is easier to control with qdbus than konsole is.