Question: Linux command top -p option can allow up to 20 processes. Is there any way that I can specify more than 20 process? 

Something like 
top -pN1 -pN2 .... -pN30

Answer: 
Try,

```
sudo port install libnewt

```

After that, you may need to add /opt/local/lib/python2.6/site-packages to PYTHONPATH as follows,

```
export PYTHONPATH=/opt/local/lib/python2.6/site-packages/

```

or

```
setenv PYTHONPATH /opt/local/lib/python2.6/site-packages/

```
There's currently an annoying issue where the `newt` Homebrew package is not correctly building the Python extensions, see [Homebrew/homebrew-core PR#37479: Fix newt python detection on mojave](https://github.com/Homebrew/homebrew-core/pull/37479). Either build the `newt` package from that PR, or have a look at the discussion on that PR for a workaround.

Essentially, it boils down to adding a patch similar to this to the Homebrew formula for `newt`:

```
     inreplace "configure", "ls /usr/include/python*/Python.h", "find /System/Library/Frameworks/Python.framework/Versions/ -name 'Python.h'"

```

... or building `newt` from the latest source code and running `./configure ... --with-python=python2.7` (why Python2.7? I didn't check myself if `byobu-config` was Python3 compliant, but the [Arch Linux AUR PKGBUILD](https://aur.archlinux.org/cgit/aur.git/tree/PKGBUILD?h=byobu) specifies Python2 as a dependency.).