Hi @Pawel Kwiatkowski, can you describe the outcome you are trying to achieve? You should be able to use a subshell if the interpreter supports it.

Hello @Brendan Dalpe
I would like redirect output to a log, eg. /tmp/file_$(date "+%d%h%g").log
When I was using this in the tee fun is not working as expected.

I was trying using '-a' arg but also is not working.

Did a little digging on this. The native function does not spawn a shell, so subshells are not supported.

However, you can customize your tee function to start a new bash shell which will allow you to run a subshell command as you want.

The file is written as expected:

Note: You might not see file timestamp rotation because we're keeping that shell open unless it exits for some reason. Just keep that in mind as you're building out the pipeline.