[OS X TeX] broken tex distribution

[Martin Costabel]

Shawn Allgeier wrote:
> My TeXshop stopped working.  When I try to compile I receive the 
> following message:
> -----
> Can't find required tool
> (null) does not exist. 

This indicates that you erased the pdflatex field in the Engine tab of 
the TeXShop preferences. Reset to the default values or write "pdflatex 
--shell-escape" in that box.

-- 
Martin