Gnome-terminal: Difference between -e and --?

Question

I'm trying to open a terminal that shows a file as it's being written. A progress percentage is written into the file and I'd like the user to see it.

Most solutions I have found for opening a new terminal say to use -e , but that returns

# Option "-e" is deprecated and might be removed in a later version of gnome-terminal
# Use "-- " to terminate the options and put the command line to execute after it.

I've seen discussion about this error, but I'm still unsure as to what the functional difference between -e and -- actually is. Scripts that I run that use -e stop working properly if I just swap them, so there's obviously something that I'm missing.

Answer 1

-e would take a single argument which would have to be parsed as a shell command, but it could precede other gnome-terminal arguments. For example,

gnome-terminal -e 'command "argument with spaces"' --some-other-gnome-terminal-option

-- is not itself an option; it's a special argument that signals the end of options. Anything following -- is ignored by gnome-terminal 's own option parser and treated like an ordinary argument. Something like

gnome-terminal -- 'command "argument with spaces"' --some-other-gnome-terminal-option

would present 2 additional arguments to gnome-terminal following the -- :

1. command "argument with spaces"
2. --some-other-gnome-terminal-option

Further, you would get an error, because gnome-terminal would attempt to run a command named command "argument with spaces" , rather than a command named command .

---

In practice, this means you can't simply replace -e with -- and call it a day. Instead, you would first move -e to the end of the options list:

gnome-terminal --some-other-gnome-terminal-option -e 'command "argument with spaces"' 

then replace -e '...' with --... . The command and each of its arguments are now distinct arguments to gnome-terminal , which removes the need for an entire layer of quoting.

gnome-terminal --some-other-gnome-terminal-option -- command "argument with spaces"