How to ignore return value different then 0 when I have set -e?

Question

I often add set -e in my bash scripts. However this time I have to call a command that returns some meaningless number instead of 0 on success. How can I tell bash to ignore the return value of this command only.

Changing the command, or changing it's code to conform to the standard is not an option.

Answer 1

true always returns a zero exit code. So you can do

command-with-meaningless-return-value || true

Answer 2

If you need to use the value of $? later, you can do:

# A test funtion to demonstrate different exit status values
$ exit_with(){ return $1; }

$ exit_with 0

$ echo $?
0

$ exit_with 4

$ echo $?
4

$ exit_with 4 || true

$ echo $?
0

# capture the exit status rather than clobber it
$ exit_with 4 || exit_status=$?

$ echo $?
0

$ echo $exit_status
4

In this case use $exit_status instead of $?. I've not found a way to do something like ?=$? or declare ?=$?