Original post: http://developer.ctrlplusv.com/2010/04/12/drupal-6-base_path-is-not-base_path/
Over the past 2 days i close to finished the theme conversion for CGX24.
I now started to build some block modules and came across that $base_path does NOT (always ?) point to the home URL.
In my themplate i sticked to call the base url via
By a typo i hoverver used
on one of my modules to get the base URL, but i quickly figured that $base_path points out the full URL to current page.
After i had a closer look on the api docs, i defined $base_path as a global first, and this brought the correct result of $base_path being then the base URL.
However, the best solution in my mind is to always use base_path() if you need to get the base URL to your drupal install.