Here is the laziest way (or homebrew way)
First install Homebrew if you haven't
brew install htop
htop 0.8 (update: now 2.0.1) from MacPorts with
sudo port install htop
Found this tutorial that shows how to do it. The steps are as follows:
$ curl -O http://themainframe.ca/wp-content/uploads/2011/06/htop.zip $ unzip htop.zip $ sudo mv htop /bin $ rm htop.zip
This binary is already pre-built so you should use caution when using executables such as this to make sure that they aren't malicious.
Building it from scratch
You can also follow these directions if you'd like to attempt to build the executable yourself. The tutorial is called:
htop for Snow Leopard. A copy of the original reference material is here on Tech Chutney.
$ git clone git://github.com/AndyA/htop-osx.git
Building this under Snow Leopard requires you to checkout the 'osx' branch:
$ cd htop-osx $ git checkout -b osx origin/osx
and set your 'CFLAGS' environmental variable to specify a 32-bit build:
$ export CFLAGS="-m32" before the actual build: $ ./autogen.sh $ ./configure $ make $ make install