[OS X TeX] Engines in TeXShop

[Richard Koch]

All this is not mysterious if you recall that TeXShop has a history. 

The original TeXShop had two buttons. Pushing one called TeX and pushing the other called LaTeX.

A few years later I discovered bibliographies, which required users to call LaTeX and then BibTeX and then LaTeX and then LaTeX. So I added a special menu command to call BibTeX. And after that, one to call MakeIndex. And then some users pointed out that there were alternatives to BibTeX, so I added preference settings so BibTeX would call the alternatives. All minor league stuff.

Then Jonathan Kew invented XeTeX. This was big league stuff, and caused me to add engines. Think of engines as mainly for the big typesetting jobs, not the minor adjunct jobs. They are called with command-T. As Herbert points out, they are shell scripts which can essentially do anything. TeXShop doesn't have rules about using only TeX Live in the engine; you can add a full path to where-ever you like.

It might make sense to convert BibTeX and MakeIndex into special kinds of engines and ignore all the history. Then there would be only one kind of job. But that hasn't happened yet.

You are free to make your own engine which calls BibTeX. Just don't think that magically, the preference settings for BibTeX or the % !... commands will  be picked up by your engine. 

Dick Koch