Ubuntu – How and why does “exec false” close the terminal

command line

I know that this is probably a relatively pointless question, but I am curious as to why exec false closes the terminal just like exit does.

I would also like to know if this is a acceptable way to close the terminal or not.

Best Answer

exec false is replacing the current shell by the execution of the command false (here not the shell builtin but /bin/false or whatever false executable that comes first in the PATH) which quickly exits. If the shell was the topmost process running in your terminal emulator, there are no more processes running inside it so the terminal emulator is closed.

This is a an acceptable alternate way to close a terminal, just like would be many similar commands:

exec true
exec sleep 0
exec echo
...

See also: what-does-an-exec-command-do

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