Exit the terminal and execute a command.

Question

I want to exit the current terminal and execute a command. Is it possible to do?

PS:: Assume that I have made a loop while true; do bash;done

Answer 1

You could execute it in a subshell with an appropriate trap. For example, if you wanted to execute echo -e '\nCommand done at the end of a while true; do true; done, you could use this:

mario@mario-K53SV:~$ (trap 'echo -e "\nCommand done"' EXIT; while true; do true; done)

The trap registers the command you defined on the EXIT event of the subshell. The parentheses are needed to make a subshell. Be aware that in case you want to generalize this, and put your commands in variables (e.g. MY_COMMAND='while true; do true; done'), you will need eval to execute them correctly. This example output shows exactly where it is useful (without eval, this wouldn't work):

mario@mario-K53SV:~$ YOUR_COMMAND="while true; do true; done"
mario@mario-K53SV:~$ EXECUTE_ON_EXIT="echo -e '\nCommand done'"
mario@mario-K53SV:~$ (trap 'eval ${EXECUTE_ON_EXIT}' EXIT; eval ${YOUR_COMMAND})
^C
Command done

mario@mario-K53SV:~$

Should you wish so, this can also be used to automatically close your terminal too, at the end of the EXIT handler command: just include kill -s SIGHUP $$ at the end of your handler (e.g. EXECUTE_ON_EXIT="echo -e '\nCommand done'; kill -s SIGHUP $$").