How to redirect standard out and standard error to a file, and standard error (only) to console at the same time

Question

I would like to direct:

• Standard out to file.
• Standard error to the same file.
• Standard error to console (as well as file).

I've seen this kind of thing:

mycommand 2>&1 | tee test.txt

But it shows standard out on the console where I only want to see errors.

Any help would be appreciated.

Answer 1

This is not optimal but it should do:

exec 3>mylogfile; mycmd 2>&1 >&3 | tee >(tee >&3);exec 3>&-;

have fun playing with this.