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bash gnome-terminal bashrc
Updated Fri, 20 May 2022 07:56:16 GMT

Open gnome terminal programmatically and execute commands after bashrc was executed


For starting my dev environment I wrote a little script. One part is to open a gnome terminal with several tabs where automatically some commands should be executed. Some of those commands depend on an already executed .bashrc. But when using

gnome-terminal --tab -e "command" --tab --tab

the command is executed before .bashrc was executed. Is there a possibility to make an automated gnome-terminal -e behave like a manually used one? (even commands like "cd /foo/bar" do not work with gnome-terminal -e)




Solution

Once gnome-terminal has started bash, it's out of the loop as far as command execution is concerned: it only manages the input and output. So you'll need bash's cooperation to run something after ~/.bashrc has been loaded.

First, in many cases, you don't actually need to execute commands after ~/.bashrc. For example, opening a terminal in a particular directory can simply be done with cd /foo/bar && gnome-terminal. You can set environment variables in a similar way: VAR=value gnome-terminal. (If your ~/.bashrc overrides environment variables, you're doing it wrong: environment variable definitions belong in ~/.profile)

To execute commands in the terminal, but before ~/.bashrc, you can do

gnome-terminal -x sh -c 'command1; command2; exec bash'

If you want to use multiple tabs, you have to use -e instead of -x. Gnome-terminal unhelpfully splits the argument of -e at spaces rather than executing it through a shell. Nonetheless, you can write a shell command if you make sure not to include spaces in it. At least with gnome-terminal 2.26, you can use tabs, though (replace <TAB> by a literal tab character):

gnome-terminal -e 'sh -c command1;command2;exec<TAB>bash'
gnome-terminal --tab -e 'sh -c command1;<TAB>exec<TAB>bash' \
               --tab -e 'sh -c command2;<TAB>exec<TAB>bash'

If you do need to run commands after ~/.bashrc, make it run the commands. For example, include the following code at the end of ~/.bashrc:

eval "$BASH_POST_RC"

Then to run a some code after (really, at the end of) your bashrc:

gnome-terminal -x sh -c BASH_POST_RC=\''command1; command2'\''; exec bash'

or (less heavy on the quoting)

BASH_POST_RC='command1; command2' gnome-terminal

Although I don't particularly recommend doing it this way, you may be interested in the techniques mentioned in How to start a terminal with certain text already input on the command-line?.





Comments (5)

  • +0 – Yes, indeed a nice trick. Never thought of that. Now I must find a way to set the BASH_POST_RC variable differently for the specific tab. And that still seems to be a problem. A simple "gnome-terminal --tab -e 'BASH_POST_RC=ls' --tab" is not possible :-( — Oct 10, 2010 at 23:41  
  • +0 – @Zardoz: Actually, you can trick gnome-terminal using tab characters (see my revised answer). Mind the multiple levels of quoting. — Oct 11, 2010 at 00:11  
  • +0 – .. it works :-) ... thanks a lot for your solution and your patience. Here my complete command (works even with those spaces in the commands: gnome-terminal --working-directory="/home/zardoz/projects/my_rails_app" --tab -e 'bash -c "export BASH_POST_RC=\"rails server\"; exec bash"' --tab -e 'bash -c "export BASH_POST_RC=\"autotest\"; exec bash"' --tab — Oct 11, 2010 at 00:44  
  • +0 – Finally made it work... After sooo many tests with quotes all the way round. Here is mine, using zsh and opening a server and a console at once: gnome-terminal --geometry=198x44 --working-directory=/home/username/Workspace/project_name --tab --title server -e 'zsh -c "export BASH_POST_RC=\"rails server\"; exec zsh"' --tab --title console -e 'zsh -c "export BASH_POST_RC=\"rails console\"; exec zsh"' — Nov 26, 2013 at 11:51  
  • +2 – @terdon No, gnome-terminal -e does not invoke a shell at all. If you run gnome-terminal -e 'sleep 9', that executes the command sleep with the argument 9, and no shell is involved. If you execute gnome-terminal -e 'sleep 9;bash' then the terminal opens and closes immediately, because sleep complains that 9;bash is not a valid time interval. You can observe what's going on with strace -f -eexecve gnome-terminal -e — Feb 04, 2016 at 12:46  


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